diff --git a/Sprint-1/1-key-exercises/1-count.js b/Sprint-1/1-key-exercises/1-count.js
index 117bcb2b6e..ec09d7fb85 100644
--- a/Sprint-1/1-key-exercises/1-count.js
+++ b/Sprint-1/1-key-exercises/1-count.js
@@ -4,3 +4,7 @@ count = count + 1;
 
 // Line 1 is a variable declaration, creating the count variable with an initial value of 0
 // Describe what line 3 is doing, in particular focus on what = is doing
+// This line (line 3), is updating the value of the count variable. The = operator is an 
+// assignment operator which assigns the value on the right (count + 1) to the variable on the left (count). 
+// count = count + 1; This operation is called increment.
+// An increment means increasing the value of a variable by 1.
\ No newline at end of file
diff --git a/Sprint-1/1-key-exercises/2-initials.js b/Sprint-1/1-key-exercises/2-initials.js
index 47561f6175..ea5ed865f2 100644
--- a/Sprint-1/1-key-exercises/2-initials.js
+++ b/Sprint-1/1-key-exercises/2-initials.js
@@ -4,8 +4,6 @@ let lastName = "Johnson";
 
 // Declare a variable called initials that stores the first character of each string.
 // This should produce the string "CKJ", but you must not write the characters C, K, or J in the code of your solution.
+let initials = firstName[0] + middleName[0] + lastName[0];
 
-let initials = ``;
-
-// https://www.google.com/search?q=get+first+character+of+string+mdn
-
+// https://www.google.com/search?q=get+first+character+of+string+mdn
\ No newline at end of file
diff --git a/Sprint-1/1-key-exercises/3-paths.js b/Sprint-1/1-key-exercises/3-paths.js
index ab90ebb28e..98ab371c3f 100644
--- a/Sprint-1/1-key-exercises/3-paths.js
+++ b/Sprint-1/1-key-exercises/3-paths.js
@@ -17,7 +17,7 @@ console.log(`The base part of ${filePath} is ${base}`);
 // Create a variable to store the dir part of the filePath variable
 // Create a variable to store the ext part of the variable
 
-const dir = ;
-const ext = ;
+const dir = filePath.slice(0, lastSlashIndex);
+const ext = base.slice(base.lastIndexOf("."));
 
 // https://www.google.com/search?q=slice+mdn
\ No newline at end of file
diff --git a/Sprint-1/1-key-exercises/4-random.js b/Sprint-1/1-key-exercises/4-random.js
index 292f83aabb..59d1d93fd1 100644
--- a/Sprint-1/1-key-exercises/4-random.js
+++ b/Sprint-1/1-key-exercises/4-random.js
@@ -7,3 +7,16 @@ const num = Math.floor(Math.random() * (maximum - minimum + 1)) + minimum;
 // Try breaking down the expression and using documentation to explain what it means
 // It will help to think about the order in which expressions are evaluated
 // Try logging the value of num and running the program several times to build an idea of what the program is doing
+
+// Math.random returns a random number between 0 (inclusive) and 1 (exclusive).
+// const minimum = 1; const maximum = 100; +1 so, 100 - 1 + 1 = 100
+// Math.random() * 100 means the decimal number will be multiplied by 100, so the range of possible values is from 0 to 99.9999...
+// Math.floor rounds the number down to the nearest whole number, so the possible values are from 0 to 99.
+// Eg. 12.9 becomes 12, 0.3 becomes 0, 99.9 becomes 99.
+// Brackets(), Multiply*, Function(Math.floor), Addition+
+// 1) Pick a random number between 0 and 1, eg. 0.5
+// 2) Multiply that number by 100, eg. 0.5 * 100 = 50
+// 3) Round that number down to the nearest whole number, eg. Math.floor(50) = 50
+// 4) Add 1 to that number, eg. 50 + 1 = 51
+
+// num represents a random whole number between 1 and 100.
\ No newline at end of file
diff --git a/Sprint-1/2-mandatory-errors/0.js b/Sprint-1/2-mandatory-errors/0.js
index cf6c5039f7..9530ff0d72 100644
--- a/Sprint-1/2-mandatory-errors/0.js
+++ b/Sprint-1/2-mandatory-errors/0.js
@@ -1,2 +1,3 @@
-This is just an instruction for the first activity - but it is just for human consumption
-We don't want the computer to run these 2 lines - how can we solve this problem?
\ No newline at end of file
+// This is just an instruction for the first activity - but it is just for human consumption
+// We don't want the computer to run these 2 lines - how can we solve this problem?
+// The forward slash is used to indicate a comment in JavaScript, so the computer will ignore these lines when running the program.
diff --git a/Sprint-1/2-mandatory-errors/1.js b/Sprint-1/2-mandatory-errors/1.js
index 7a43cbea76..4c570b531a 100644
--- a/Sprint-1/2-mandatory-errors/1.js
+++ b/Sprint-1/2-mandatory-errors/1.js
@@ -1,4 +1,10 @@
 // trying to create an age variable and then reassign the value by 1
 
-const age = 33;
+let age = 33;
 age = age + 1;
+console.log(age);
+
+// The code above will output 34, because we are reassigning the value of age 
+// to be the current value of age plus 1. So, 33 + 1 = 34.
+// The error in the code is that it was trying to reassign a value to a variable 
+// that was declared with let. This is not allowed in JavaScript.
\ No newline at end of file
diff --git a/Sprint-1/2-mandatory-errors/2.js b/Sprint-1/2-mandatory-errors/2.js
index e09b89831d..88686319d1 100644
--- a/Sprint-1/2-mandatory-errors/2.js
+++ b/Sprint-1/2-mandatory-errors/2.js
@@ -1,5 +1,8 @@
 // Currently trying to print the string "I was born in Bolton" but it isn't working...
 // what's the error ?
 
-console.log(`I was born in ${cityOfBirth}`);
 const cityOfBirth = "Bolton";
+console.log(`I was born in ${cityOfBirth}`);
+
+// The error happens because cityOfBirth is used before it is defined. JavaScript runs 
+// code from top to bottom, so the variable must be declared first.
\ No newline at end of file
diff --git a/Sprint-1/2-mandatory-errors/3.js b/Sprint-1/2-mandatory-errors/3.js
index ec101884db..b5571ab658 100644
--- a/Sprint-1/2-mandatory-errors/3.js
+++ b/Sprint-1/2-mandatory-errors/3.js
@@ -1,5 +1,5 @@
-const cardNumber = 4533787178994213;
-const last4Digits = cardNumber.slice(-4);
+// const cardNumber = 4533787178994213;
+// const last4Digits = cardNumber.slice(-4);
 
 // The last4Digits variable should store the last 4 digits of cardNumber
 // However, the code isn't working
@@ -7,3 +7,15 @@ const last4Digits = cardNumber.slice(-4);
 // Then run the code and see what error it gives.
 // Consider: Why does it give this error? Is this what I predicted? If not, what's different?
 // Then try updating the expression last4Digits is assigned to, in order to get the correct value
+
+// Prediction: The code will not work because slice() is being used on cardNumber, which is a number.
+// The slice() method only works on strings or arrays, not numbers.
+// So I predict JavaScript will throw an error saying that slice is not a function for a number.
+
+const cardNumber = 4533787178994213;
+const last4Digits = cardNumber.toString().slice(-4);
+console.log(last4Digits);
+
+// After running the code, I got the output "4213", which is the last 4 digits of the card number.
+// This is what i expected.
+//testing
\ No newline at end of file
diff --git a/Sprint-1/2-mandatory-errors/4.js b/Sprint-1/2-mandatory-errors/4.js
index 21dad8c5d1..6605121098 100644
--- a/Sprint-1/2-mandatory-errors/4.js
+++ b/Sprint-1/2-mandatory-errors/4.js
@@ -1,2 +1,12 @@
-const 12HourClockTime = "20:53";
-const 24hourClockTime = "08:53";
\ No newline at end of file
+// const 12HourClockTime = "20:53";
+// const 24hourClockTime = "08:53";
+
+// Variables cannot start with a number.
+// When JavaScript tries to run the code, it throws a SyntaxError.
+// To fix the error we can rename the variable to start with a letter, a 
+// underescore_ or a dollar sign $ instead of a number.
+
+const twelveHourClockTime = "8:53";
+const twentyFourHourClockTime = "08:53";
+
+// I changed the time to match the 12 and 24 hr clock format.
\ No newline at end of file
diff --git a/Sprint-1/3-mandatory-interpret/1-percentage-change.js b/Sprint-1/3-mandatory-interpret/1-percentage-change.js
index e24ecb8e18..5999a1e785 100644
--- a/Sprint-1/3-mandatory-interpret/1-percentage-change.js
+++ b/Sprint-1/3-mandatory-interpret/1-percentage-change.js
@@ -2,7 +2,7 @@ let carPrice = "10,000";
 let priceAfterOneYear = "8,543";
 
 carPrice = Number(carPrice.replaceAll(",", ""));
-priceAfterOneYear = Number(priceAfterOneYear.replaceAll("," ""));
+priceAfterOneYear = Number(priceAfterOneYear.replaceAll(",",""));
 
 const priceDifference = carPrice - priceAfterOneYear;
 const percentageChange = (priceDifference / carPrice) * 100;
@@ -11,12 +11,49 @@ console.log(`The percentage change is ${percentageChange}`);
 
 // Read the code and then answer the questions below
 
-// a) How many function calls are there in this file? Write down all the lines where a function call is made
+// a) How many function calls are there in this file? Write down all the 
+// lines where a function call is made
+
+// There are 5 function calls in this file. They are on lines 1, 2, 4, and 5. 
+// The functions being called are replaceAll() and Number(). 
+// Line 4: replaceAll and Number (2)
+// Line 5: replaceAll and Number (2)
+// Line 10: console.log (1)
+
+
+
+// b) Run the code and identify the line where the error is coming from - why is 
+// this error occurring? How can you fix this problem?
+
+// The error is occuring on line 5. It is occuring because there is a missing 
+// comma between the replaceAll "".
+// We can fix this by adding a comma between the two empty strings in the replaceAll 
+// function on line 5, like this: priceAfterOneYear = Number(priceAfterOneYear.replaceAll(",", ""));  
+
 
-// b) Run the code and identify the line where the error is coming from - why is this error occurring? How can you fix this problem?
 
 // c) Identify all the lines that are variable reassignment statements
 
+// carPrice = Number(carPrice.replaceAll(",", ""));
+// priceAfterOneYear = Number(priceAfterOneYear.replaceAll("," ""));
+
+
+
 // d) Identify all the lines that are variable declarations
 
-// e) Describe what the expression Number(carPrice.replaceAll(",","")) is doing - what is the purpose of this expression?
+// Lines 1,2,7 and 8.
+// let carPrice = "10,000";
+// let priceAfterOneYear = "8,543";
+// const priceDifference = carPrice - priceAfterOneYear;
+// const percentageChange = (priceDifference / carPrice) * 100;
+
+
+
+// e) Describe what the expression Number(carPrice.replaceAll(",","")) is doing - 
+// what is the purpose of this expression?
+
+// carPrice.replaceAll(",", "") - Replaces all commas "," in the string with 
+// nothing "". e.g "10,000" becomes "10000".
+// Number() - Converts the resulting string "10000" into the number 10000.
+// The purpose of this is to take a string with commas (like "10,000") and turn 
+// it into a number (10000) that we can do math with.
\ No newline at end of file
diff --git a/Sprint-1/3-mandatory-interpret/2-time-format.js b/Sprint-1/3-mandatory-interpret/2-time-format.js
index 47d2395587..d2d3793a44 100644
--- a/Sprint-1/3-mandatory-interpret/2-time-format.js
+++ b/Sprint-1/3-mandatory-interpret/2-time-format.js
@@ -1,25 +1,78 @@
-const movieLength = 8784; // length of movie in seconds
+//const movieLength = 8784; // length of movie in seconds
 
-const remainingSeconds = movieLength % 60;
-const totalMinutes = (movieLength - remainingSeconds) / 60;
+//const remainingSeconds = movieLength % 60;
+//const totalMinutes = (movieLength - remainingSeconds) / 60;
 
-const remainingMinutes = totalMinutes % 60;
-const totalHours = (totalMinutes - remainingMinutes) / 60;
+//const remainingMinutes = totalMinutes % 60;
+//const totalHours = (totalMinutes - remainingMinutes) / 60;
 
-const result = `${totalHours}:${remainingMinutes}:${remainingSeconds}`;
-console.log(result);
+//const result = `${totalHours}:${remainingMinutes}:${remainingSeconds}`;
+//console.log(result);
 
 // For the piece of code above, read the code and then answer the following questions
 
 // a) How many variable declarations are there in this program?
 
+// There are 6 variable declarations in this program. They are on lines 1, 3, 5, 7, 
+// 9 and 11. The variables being declared are movieLength, remainingSeconds, totalMinutes, 
+// remainingMinutes, totalHours and result.
+
+
+
 // b) How many function calls are there?
 
+// There is 1 function calls in this program. It is on lines 10. The functions is the 
+// console.log().
+
+
+
 // c) Using documentation, explain what the expression movieLength % 60 represents
 // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Arithmetic_Operators
 
+// % is the remainder operator.
+// movieLength % 60 - This gives the remainder when movieLength is divided by 60.
+// Since there are 60 seconds in a minute, this tells us how many leftover seconds there are 
+// after counting full minutes.
+// For example, 8784 % 60 = 24. So there are 24 seconds left after counting the minutes.
+
+
+
 // d) Interpret line 4, what does the expression assigned to totalMinutes mean?
 
+// movieLength - remainingSecond - This gives the total number of seconds in the movie after 
+// removing the leftover seconds.
+// Divide by 60 - this converst the seconds into total full minutes. eg. (8784 - 24) = 8760, 8760 / 60 = 146.
+
+
+
 // e) What do you think the variable result represents? Can you think of a better name for this variable?
 
-// f) Try experimenting with different values of movieLength. Will this code work for all values of movieLength? Explain your answer
+// The variable result is a string that represents the movie length in hours:minutes:seconds
+// For example: 2:26:24 (2 hours, 26 minutes, 24 seconds)
+// Better name can be movieDurationString.
+
+
+
+// f) Try experimenting with different values of movieLength. Will this code work for all values of movieLength? 
+// Explain your answer
+
+// This code will work for all positive integer values of movieLength. It will correctly calculate the hours,
+// minutes and seconds for any length of movie. However, if movieLength is negative or not an integer, the 
+// code may not work as intended. For example, if movieLength is -100, the calculations will not make sense 
+// in the context of a movie length. If movieLength is a decimal, it may also cause issues with the calculations.
+
+const movieLength = 65;
+
+const remainingSeconds = movieLength % 60;
+const totalMinutes = (movieLength - remainingSeconds) / 60;
+
+const remainingMinutes = totalMinutes % 60;
+const totalHours = (totalMinutes - remainingMinutes) / 60;
+
+const formattedHours = String(totalHours).padStart(2, "0");
+const formattedMinutes = String(remainingMinutes).padStart(2, "0");
+const formattedSeconds = String(remainingSeconds).padStart(2, "0");
+
+const movieDurationString = `${formattedHours}:${formattedMinutes}:${formattedSeconds}`;
+
+console.log(movieDurationString); // 00:01:05
diff --git a/Sprint-1/3-mandatory-interpret/3-to-pounds.js b/Sprint-1/3-mandatory-interpret/3-to-pounds.js
index 60c9ace69a..fd2c67afa8 100644
--- a/Sprint-1/3-mandatory-interpret/3-to-pounds.js
+++ b/Sprint-1/3-mandatory-interpret/3-to-pounds.js
@@ -25,3 +25,18 @@ console.log(`£${pounds}.${pence}`);
 
 // To begin, we can start with
 // 1. const penceString = "399p": initialises a string variable with the value "399p"
+// 2. const penceStringWithoutTrailingP = penceString.substring(0, penceString.length - 1): creates 
+// a new string variable that contains the original string without the last character (the "p"). 
+// 3. const paddedPenceNumberString = penceStringWithoutTrailingP.padStart(3, "0"): creates a new 
+// string variable that pads the previous string with leading zeros until it is at least 3 characters 
+// long. eg. "45" becomes "045" and "7" becomes "007".
+// 4. const pounds = paddedPenceNumberString.substring(0, paddedPenceNumberString.length - 2): creates 
+// a new string variable that contains the first part of the padded string, which represents the pounds.
+// It takes all characters except the last two. eg. "045" becomes "0" and "399" becomes "3".
+// 5. const pence = paddedPenceNumberString.substring(paddedPenceNumberString.length - 2).padEnd(2, "0"): 
+// creates a new string variable that contains the last two characters of the padded string, which represents 
+// the pence. It also pads it with trailing zeros if necessary to ensure it is 2 characters long. eg. "045" 
+// becomes "45" and "7" becomes "70".
+// 6. console.log(`£${pounds}.${pence}`): outputs the final price in pounds and pence format to the console. 
+// For example, if penceString is "399p", it will output "£3.99". If penceString is "45p", it will output "£0.45". 
+// If penceString is "7p", it will output "£0.07".
diff --git a/Sprint-2/1-key-errors/0.js b/Sprint-2/1-key-errors/0.js
index 653d6f5a07..641b77bca5 100644
--- a/Sprint-2/1-key-errors/0.js
+++ b/Sprint-2/1-key-errors/0.js
@@ -1,13 +1,38 @@
 // Predict and explain first...
-//  =============> write your prediction here
+// I predict when this code runs, there will be a SyntaxError before the function executes. 
+// This is because the identifier 'str' has already been declared.
 
 // call the function capitalise with a string input
+// capitalise("hello");
+
+
 // interpret the error message and figure out why an error is occurring
+// Uncaught SyntaxError: Unexpected identifier 'string' - this is the error message. 
+// This error is occuring because the variable 'str' is being redeclared within the 
+// function, which is not allowed in JavaScript.
+// The duplicate use if 'str' is causing the syntax error.
+
+
+//function capitalise(str) {
+  //let str = `${str[0].toUpperCase()}${str.slice(1)}`;
+  //return str;
+//}
+
+// The issue is variable redeclaration.
+// str is the function parameter.
+// let str tries to create a new variable with the same name.
+// JavaScript does not allow redeclaring a variable in the same scope.
+// As a result, the code throws a SyntaxError when it encounters the second 'str' declaration.
+
+// New code without the error:
 
+// 0.js — fully fixed version
 function capitalise(str) {
-  let str = `${str[0].toUpperCase()}${str.slice(1)}`;
-  return str;
+  if (!str) return str; // handles empty string
+  return str[0].toUpperCase() + str.slice(1);
 }
 
-// =============> write your explanation here
-// =============> write your new code here
+// Test it
+console.log(capitalise("hello")); // should print "Hello"
+console.log(capitalise("world")); // should print "World"
+console.log(capitalise(""));      // should print ""
diff --git a/Sprint-2/1-key-errors/1.js b/Sprint-2/1-key-errors/1.js
index f2d56151f4..2f8e039ff0 100644
--- a/Sprint-2/1-key-errors/1.js
+++ b/Sprint-2/1-key-errors/1.js
@@ -1,20 +1,32 @@
 // Predict and explain first...
-
 // Why will an error occur when this program runs?
-// =============> write your prediction here
+// I predict an error will occur when this program runs because the variable 'decimalNumber' is already declared inside the function 'convertToPercentage' and cannot be redeclared.
 
 // Try playing computer with the example to work out what is going on
+// When the 'function convertToPercentage(decimalNumber)' is created, 
+// Javascript already creates a variable called decimalNumber. then, inside the function, 
+// 'const decimalNumber = 0.5' tries to create another variable with the same name. This 
+// casues a syntax error because you cannot declare two variables with the same name in the same scope. 
 
-function convertToPercentage(decimalNumber) {
-  const decimalNumber = 0.5;
-  const percentage = `${decimalNumber * 100}%`;
+// function convertToPercentage(decimalNumber) {
+  // const decimalNumber = 0.5;
+  // const percentage = `${decimalNumber * 100}%`;
 
-  return percentage;
-}
+  // return percentage;
+// }
 
-console.log(decimalNumber);
+// console.log(decimalNumber);
 
-// =============> write your explanation here
+// Write your explanation here
+// I redelcared the parameter decimalNumber using const. 
+// I tried to log decimalNumber outside its scope.
+// The variables declared inside the function are not available outside unless they are returned.
 
 // Finally, correct the code to fix the problem
-// =============> write your new code here
+
+function convertToPercentage(decimalNumber) {
+  const percentage = `${decimalNumber * 100}%`;
+  return percentage;
+}
+
+console.log(convertToPercentage(0.5)); // "50%"
diff --git a/Sprint-2/1-key-errors/2.js b/Sprint-2/1-key-errors/2.js
index aad57f7cfe..4baed256e4 100644
--- a/Sprint-2/1-key-errors/2.js
+++ b/Sprint-2/1-key-errors/2.js
@@ -1,20 +1,28 @@
-
 // Predict and explain first BEFORE you run any code...
+// This function should square any number but instead we're going to get an error
 
-// this function should square any number but instead we're going to get an error
-
-// =============> write your prediction of the error here
+// Write your prediction of the error here:
+// I predict that the error will be a syntax error because the parameter '3' is not a valid variable name.
+// When you define a function,, the thing inside the parentahese must be a parameter name, NOT a number.
 
-function square(3) {
-    return num * num;
-}
+// function square(3) {
+   // return num * num;
+// }
 
-// =============> write the error message here
+// Write the error message here
+// SyntaxError: Unexpected number
 
-// =============> explain this error message here
+// Explain the error messge here:
+// When defining a function, inside the parentheses, you need to put a parameter name, which is a variable.
+// In this case, '3' is not a valid parameter name because it is a number, not a variable. 
+// This causes a syntax error because Javascript expects a name, not a number.
 
 // Finally, correct the code to fix the problem
+// Write your new code here
 
-// =============> write your new code here
-
+function square(num) {
+    return num * num;
+}
 
+console.log(square(3));  // 9
+console.log(square(5));  // 25
diff --git a/Sprint-2/2-mandatory-debug/0.js b/Sprint-2/2-mandatory-debug/0.js
index b27511b417..3d0b813af8 100644
--- a/Sprint-2/2-mandatory-debug/0.js
+++ b/Sprint-2/2-mandatory-debug/0.js
@@ -1,14 +1,24 @@
-// Predict and explain first...
+// Predict and explain first...write your prediction here
+// I predict, when the code runs, it will print 320, but it will also print "The result of multiplying 10 and 32 is undefined".
 
-// =============> write your prediction here
+//function multiply(a, b) {
+//  console.log(a * b);
+// }
+
+// console.log(`The result of multiplying 10 and 32 is ${multiply(10, 32)}`);
+
+// Write your explanation here
+// The function multiply(a, b) logs the result of a * b to the console but does not return a value.
+// When multiply(10, 32) is called within the template literal, it logs 320 to the console but returns undefined.
+// Therefore, inside the template literal, the value is undefined, which is why the final output 
+// becomes "The result of multiplying 10 and 32 is undefined".
+
+// Finally, correct the code to fix the problem
+// Write your new code here
+// To fix the problem, the function should return the result instead of logging it.
 
 function multiply(a, b) {
-  console.log(a * b);
+  return a * b;
 }
 
 console.log(`The result of multiplying 10 and 32 is ${multiply(10, 32)}`);
-
-// =============> write your explanation here
-
-// Finally, correct the code to fix the problem
-//  =============> write your new code here
diff --git a/Sprint-2/2-mandatory-debug/1.js b/Sprint-2/2-mandatory-debug/1.js
index 37cedfbcfd..c427fdf74e 100644
--- a/Sprint-2/2-mandatory-debug/1.js
+++ b/Sprint-2/2-mandatory-debug/1.js
@@ -1,13 +1,26 @@
-// Predict and explain first...
-//  =============> write your prediction here
+// Predict and explain first...write your prediction here
+// I think the code will return undefined.
 
-function sum(a, b) {
-  return;
-  a + b;
-}
+//function sum(a, b) {
+ // return;
+ // a + b;
+//}
 
-console.log(`The sum of 10 and 32 is ${sum(10, 32)}`);
+//console.log(`The sum of 10 and 32 is ${sum(10, 32)}`);
+
+// Write your explanation here
+// When JavaScript sees the 'return' statement, it immediately stops the function. 
+// This is called terminating the function.
+// It does NOT continue to the next line.
+// So this part, 'a+b;' never runs. To return the sum of a and b, we need to put it 
+// on the same line as the return.
+// Like the: 'return a + b;'
 
-// =============> write your explanation here
 // Finally, correct the code to fix the problem
 //  =============> write your new code here
+
+function sum(a, b) {
+  return a + b;
+}
+
+console.log(`The sum of 10 and 32 is ${sum(10, 32)}`);
diff --git a/Sprint-2/2-mandatory-debug/2.js b/Sprint-2/2-mandatory-debug/2.js
index 57d3f5dc35..793489ed85 100644
--- a/Sprint-2/2-mandatory-debug/2.js
+++ b/Sprint-2/2-mandatory-debug/2.js
@@ -1,24 +1,45 @@
 // Predict and explain first...
 
 // Predict the output of the following code:
-// =============> Write your prediction here
+// Write your prediction here
+// I think the output will be 'The last digit of 42 is 2', 'The last digit of 105 is 5', and 'The last digit of 806 is 6'.
+// I think this will happen because the getLastDigit function is supposed to take a number, convert it to a string, and 
+// then return the last charecter of that string, which should be the last digit. 
 
-const num = 103;
+//const num = 103;
 
-function getLastDigit() {
-  return num.toString().slice(-1);
+//function getLastDigit() {
+//  return num.toString().slice(-1);
+//}
+
+//console.log(`The last digit of 42 is ${getLastDigit(42)}`);
+//console.log(`The last digit of 105 is ${getLastDigit(105)}`);
+//console.log(`The last digit of 806 is ${getLastDigit(806)}`);
+
+// Now run the code and compare the output to your prediction
+// Write the output here
+// The output is:
+// The last digit of 42 is 3
+// The last digit of 105 is 3
+// The last digit of 806 is 3
+
+// Explain why the output is the way it is
+// write your explanation here
+// The output is 3 for all numbers because the function getLastDigit is not taking any parameters. It always uses the 
+// global variable `num` which is set to 103. So it always returns the last digit of 103, which is 3.
+
+// Finally, correct the code to fix the problem
+// Write your new code here
+
+function getLastDigit(number) {
+  return number.toString().slice(-1);
 }
 
 console.log(`The last digit of 42 is ${getLastDigit(42)}`);
 console.log(`The last digit of 105 is ${getLastDigit(105)}`);
 console.log(`The last digit of 806 is ${getLastDigit(806)}`);
 
-// Now run the code and compare the output to your prediction
-// =============> write the output here
-// Explain why the output is the way it is
-// =============> write your explanation here
-// Finally, correct the code to fix the problem
-// =============> write your new code here
 
 // This program should tell the user the last digit of each number.
 // Explain why getLastDigit is not working properly - correct the problem
+// The function did not accept a parameter. It was a fixed variable (num = 103), so it always returned the last digit of 103.
diff --git a/Sprint-2/3-mandatory-implement/1-bmi.js b/Sprint-2/3-mandatory-implement/1-bmi.js
index 17b1cbde1b..c2b35cc719 100644
--- a/Sprint-2/3-mandatory-implement/1-bmi.js
+++ b/Sprint-2/3-mandatory-implement/1-bmi.js
@@ -14,6 +14,30 @@
 // Then when we call this function with the weight and height
 // It should return their Body Mass Index to 1 decimal place
 
-function calculateBMI(weight, height) {
+//function calculateBMI(weight, height) {
     // return the BMI of someone based off their weight and height
-}
\ No newline at end of file
+// }
+
+// Notes:
+// BMI =  weight ÷ (height x height)                                        
+// eg. BMI = 70kg ÷ (1.73m x 1.73)
+// BMI = 70kg ÷ 2.99
+// BMI = 23.41
+// BMI = 23.4 (to 1 decimal place)
+
+// I need to:
+// 1. Square the height
+// 2. Divide weight by squared height
+// 3. Round the result to 1 decimal place
+// 4. Return the result 
+
+function calculateBMI(weight, height) {
+    const bmi = weight / (height * height);
+    return bmi.toFixed(1);
+}
+
+console.log(calculateBMI(70, 1.73));
+
+
+
+//toFixed(1) tells JavaScript to round the number to 1 decimal place.
\ No newline at end of file
diff --git a/Sprint-2/3-mandatory-implement/2-cases.js b/Sprint-2/3-mandatory-implement/2-cases.js
index 5b0ef77ad9..154adbac0a 100644
--- a/Sprint-2/3-mandatory-implement/2-cases.js
+++ b/Sprint-2/3-mandatory-implement/2-cases.js
@@ -14,3 +14,24 @@
 // You will need to come up with an appropriate name for the function
 // Use the MDN string documentation to help you find a solution
 // This might help https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/toUpperCase
+
+// NOTES: 
+// "hello there" should become "HELLO_THERE"
+// I need to turn all letters into CAPITALS and replace the space " " with underscore "-"
+
+// From the MDN documentation:
+// I can use the toUpperCase() to turn the tring into all CAPS.
+// I can use the replaceAll() to replace all the spaces with underscores.
+
+// Good function name:
+// toUpperSnakeCase - this name is decriptive and indicates that the function will convert a string to upper snake case.
+
+function toUpperSnakeCase(str) {
+    return str.toUpperCase().replaceAll(" ", "_");
+}
+
+console.log(toUpperSnakeCase("hello there"));
+// HELLO_THERE
+
+console.log(toUpperSnakeCase("lord of the rings"));
+// LORD_OF_THE_RINGS
\ No newline at end of file
diff --git a/Sprint-2/3-mandatory-implement/3-to-pounds.js b/Sprint-2/3-mandatory-implement/3-to-pounds.js
index 6265a1a703..75f761c9df 100644
--- a/Sprint-2/3-mandatory-implement/3-to-pounds.js
+++ b/Sprint-2/3-mandatory-implement/3-to-pounds.js
@@ -1,6 +1,63 @@
 // In Sprint-1, there is a program written in interpret/to-pounds.js
 
+// ORIGINAL CODE:
+//const penceString = "399p";
+
+//const penceStringWithoutTrailingP = penceString.substring(
+//  0,
+//  penceString.length - 1
+//);
+
+//const paddedPenceNumberString = penceStringWithoutTrailingP.padStart(3, "0");
+//const pounds = paddedPenceNumberString.substring(
+ // 0,
+ // paddedPenceNumberString.length - 2
+//);
+
+//const pence = paddedPenceNumberString
+  //.substring(paddedPenceNumberString.length - 2)
+  //.padEnd(2, "0");
+
+//console.log(`£${pounds}.${pence}`);
+
+
 // You will need to take this code and turn it into a reusable block of code.
 // You will need to declare a function called toPounds with an appropriately named parameter.
 
-// You should call this function a number of times to check it works for different inputs
+// You should call this function a number of times to check it works for different inputs.
+// For example:
+// toPounds("399p") should return "£3.99"
+// toPounds("45p") should return "£0.45"
+// toPounds("9p") should return "£0.09"
+// toPounds("1200p") should return "£12.00"
+
+// The current code removes the "p", makes sur ethe number has at least 3 digits, splits pounds and 
+// pences and prints it in money format.
+// Right now, it only works for "399p". I need it to work for "5p" and "1234p".
+// I need to turn it into a function. eg. 'function toPounds(penceString)'. penceString clearly 
+// decribes what the input is.
+
+function toPounds(penceString) {
+  const penceStringWithoutTrailingP = penceString.substring(
+    0,
+    penceString.length - 1
+  );
+
+  const paddedPenceNumberString = penceStringWithoutTrailingP.padStart(3, "0");
+
+  const pounds = paddedPenceNumberString.substring(
+    0,
+    paddedPenceNumberString.length - 2
+  );
+
+  const pence = paddedPenceNumberString
+    .substring(paddedPenceNumberString.length - 2)
+    .padEnd(2, "0");
+
+  return `£${pounds}.${pence}`;
+}
+
+console.log(toPounds("399p"));  // £3.99
+console.log(toPounds("45p"));   // £0.45
+console.log(toPounds("9p"));    // £0.09
+console.log(toPounds("1200p")); // £12.00
\ No newline at end of file
diff --git a/Sprint-2/4-mandatory-interpret/time-format.js b/Sprint-2/4-mandatory-interpret/time-format.js
index 7c98eb0e8c..168c441a98 100644
--- a/Sprint-2/4-mandatory-interpret/time-format.js
+++ b/Sprint-2/4-mandatory-interpret/time-format.js
@@ -10,25 +10,37 @@ function formatTimeDisplay(seconds) {
 
   return `${pad(totalHours)}:${pad(remainingMinutes)}:${pad(remainingSeconds)}`;
 }
+console.log(formatTimeDisplay(61));
+//testing
+//console.log(formatTimeDisplay(3661)); // 01:01:01
+//console.log(formatTimeDisplay(45));   // 00:00:45
+//console.log(formatTimeDisplay(3600)); // 01:00:00
+
+
 
 // You will need to play computer with this example - use the Python Visualiser https://pythontutor.com/visualize.html#mode=edit
 // to help you answer these questions
 
+// NOTES: 
+// This code converst seconds into HH:MM:SS and it uses pad() to make sure every number has 2 digits. e.g. 1 = "01". 0 = "00".
+// 
+
+
 // Questions
 
 // a) When formatTimeDisplay is called how many times will pad be called?
-// =============> write your answer here
+// pad will be called 3 times. pad(totalHours), pad(remainingMinutes) and pad(remainingSeconds).
 
 // Call formatTimeDisplay with an input of 61, now answer the following:
 
 // b) What is the value assigned to num when pad is called for the first time?
-// =============> write your answer here
+// num = 0
 
 // c) What is the return value of pad is called for the first time?
-// =============> write your answer here
+// Return value = 00.
 
 // d) What is the value assigned to num when pad is called for the last time in this program?  Explain your answer
-// =============> write your answer here
+// num = 1 because 61 seconds has 1 second remaining after removing 1 minute (60 seconds).
 
 // e) What is the return value assigned to num when pad is called for the last time in this program?  Explain your answer
-// =============> write your answer here
+// "01" because 1 is padded to 2 digits.
diff --git a/Sprint-2/5-stretch-extend/format-time.js b/Sprint-2/5-stretch-extend/format-time.js
index 32a32e66b8..10af29b351 100644
--- a/Sprint-2/5-stretch-extend/format-time.js
+++ b/Sprint-2/5-stretch-extend/format-time.js
@@ -2,24 +2,88 @@
 // Make sure to do the prep before you do the coursework
 // Your task is to write tests for as many different groups of input data or edge cases as you can, and fix any bugs you find.
 
+//function formatAs12HourClock(time) {
+  //const hours = Number(time.slice(0, 2));
+  //if (hours > 12) {
+    //return `${hours - 12}:00 pm`;
+  //}
+  //return `${time} am`;
+//}
+
+//const currentOutput = formatAs12HourClock("08:00");
+//const targetOutput = "08:00 am";
+//console.assert(
+  //currentOutput === targetOutput,
+  //`current output: ${currentOutput}, target output: ${targetOutput}`
+//);
+
+//const currentOutput2 = formatAs12HourClock("23:00");
+//const targetOutput2 = "11:00 pm";
+//console.assert(
+  //currentOutput2 === targetOutput2,
+  //`current output: ${currentOutput2}, target output: ${targetOutput2}`
+//);
+
+// Bug 1: Minutes are hardcoded for PM. It always uses :00 for PM. If the input is "23:45", the output becomes "11:00 pm".
+// Bug 2: AM hours are notconverted to 12 hour format. It works for "8:00" but "00:30" becomes "00:30" when it should be "12:30 am".
+// Bug 3: 12PM and 12AM are not handled correctly. "12:00" becomes "12:00 am" whjen it should be "12:00 pm", and "00:00" becomes "00:00 am" when it should be "12:00 am".
+
 function formatAs12HourClock(time) {
-  const hours = Number(time.slice(0, 2));
-  if (hours > 12) {
-    return `${hours - 12}:00 pm`;
+  let [hours, minutes] = time.split(":");
+  hours = Number(hours);
+  let period = "am";
+
+  if (hours === 0) {
+    hours = 12; // midnight
+  } else if (hours === 12) {
+    period = "pm"; // noon
+  } else if (hours > 12) {
+    hours -= 12;
+    period = "pm";
   }
-  return `${time} am`;
+
+  const paddedHours = hours.toString().padStart(2, "0");
+
+  return `${paddedHours}:${minutes} ${period}`;
 }
 
-const currentOutput = formatAs12HourClock("08:00");
-const targetOutput = "08:00 am";
-console.assert(
-  currentOutput === targetOutput,
-  `current output: ${currentOutput}, target output: ${targetOutput}`
-);
-
-const currentOutput2 = formatAs12HourClock("23:00");
-const targetOutput2 = "11:00 pm";
-console.assert(
-  currentOutput2 === targetOutput2,
-  `current output: ${currentOutput2}, target output: ${targetOutput2}`
-);
+//testing the function with various inputs.
+//console.log(formatAs12HourClock("08:00")); // 08:00 am
+//console.log(formatAs12HourClock("23:00")); // 11:00 pm
+//console.log(formatAs12HourClock("00:30")); // 12:30 am
+//console.log(formatAs12HourClock("12:15")); // 12:15 pm
+//console.log(formatAs12HourClock("13:45")); // 01:45 pm
+//console.log(formatAs12HourClock("11:59")); // 11:59 am
+//console.log(formatAs12HourClock("12:00")); // 12:00 pm
+
+import { formatAs12HourClock } from "./formatAs12HourClock";
+
+describe("formatAs12HourClock", () => {
+test("formats morning time correctly", () => {
+expect(formatAs12HourClock("08:00")).toBe("08:00 am");
+});
+
+test("formats evening time correctly", () => {
+expect(formatAs12HourClock("23:00")).toBe("11:00 pm");
+});
+
+test("formats midnight correctly", () => {
+expect(formatAs12HourClock("00:30")).toBe("12:30 am");
+});
+
+test("formats noon correctly", () => {
+expect(formatAs12HourClock("12:15")).toBe("12:15 pm");
+});
+
+test("formats afternoon time correctly", () => {
+expect(formatAs12HourClock("13:45")).toBe("01:45 pm");
+});
+
+test("formats late morning correctly", () => {
+expect(formatAs12HourClock("11:59")).toBe("11:59 am");
+});
+
+test("formats exactly noon", () => {
+expect(formatAs12HourClock("12:00")).toBe("12:00 pm");
+});
+});
\ No newline at end of file
diff --git a/Sprint-3/1-implement-and-rewrite-tests/implement/1-get-angle-type.js b/Sprint-3/1-implement-and-rewrite-tests/implement/1-get-angle-type.js
index 9e05a871e2..72c31b6900 100644
--- a/Sprint-3/1-implement-and-rewrite-tests/implement/1-get-angle-type.js
+++ b/Sprint-3/1-implement-and-rewrite-tests/implement/1-get-angle-type.js
@@ -1,37 +1,10 @@
-// Implement a function getAngleType
-//
-// When given an angle in degrees, it should return a string indicating the type of angle:
-// - "Acute angle" for angles greater than 0° and less than 90°
-// - "Right angle" for exactly 90°
-// - "Obtuse angle" for angles greater than 90° and less than 180°
-// - "Straight angle" for exactly 180°
-// - "Reflex angle" for angles greater than 180° and less than 360°
-// - "Invalid angle" for angles outside the valid range.
-
-// Assumption: The parameter is a valid number. (You do not need to handle non-numeric inputs.)
-
-// Acceptance criteria:
-// After you have implemented the function, write tests to cover all the cases, and
-// execute the code to ensure all tests pass.
-
 function getAngleType(angle) {
-  // TODO: Implement this function
+  if (angle <= 0 || angle >= 360) return "Invalid angle";
+  if (angle > 0 && angle < 90) return "Acute angle";
+  if (angle === 90) return "Right angle";
+  if (angle > 90 && angle < 180) return "Obtuse angle";
+  if (angle === 180) return "Straight angle";
+  if (angle > 180 && angle < 360) return "Reflex angle";
 }
 
-// The line below allows us to load the getAngleType function into tests in other files.
-// This will be useful in the "rewrite tests with jest" step.
 module.exports = getAngleType;
-
-// This helper function is written to make our assertions easier to read.
-// If the actual output matches the target output, the test will pass
-function assertEquals(actualOutput, targetOutput) {
-  console.assert(
-    actualOutput === targetOutput,
-    `Expected ${actualOutput} to equal ${targetOutput}`
-  );
-}
-
-// TODO: Write tests to cover all cases, including boundary and invalid cases.
-// Example: Identify Right Angles
-const right = getAngleType(90);
-assertEquals(right, "Right angle");
diff --git a/Sprint-3/1-implement-and-rewrite-tests/implement/2-is-proper-fraction.js b/Sprint-3/1-implement-and-rewrite-tests/implement/2-is-proper-fraction.js
index 970cb9b641..7d009fced3 100644
--- a/Sprint-3/1-implement-and-rewrite-tests/implement/2-is-proper-fraction.js
+++ b/Sprint-3/1-implement-and-rewrite-tests/implement/2-is-proper-fraction.js
@@ -1,33 +1,6 @@
-// Implement a function isProperFraction,
-// when given two numbers, a numerator and a denominator, it should return true if
-// the given numbers form a proper fraction, and false otherwise.
-
-// Assumption: The parameters are valid numbers (not NaN or Infinity).
-
-// Note: If you are unfamiliar with proper fractions, please look up its mathematical definition.
-
-// Acceptance criteria:
-// After you have implemented the function, write tests to cover all the cases, and
-// execute the code to ensure all tests pass.
-
 function isProperFraction(numerator, denominator) {
-  // TODO: Implement this function
+  if (denominator === 0) return false;
+  return numerator < denominator;
 }
 
-// The line below allows us to load the isProperFraction function into tests in other files.
-// This will be useful in the "rewrite tests with jest" step.
 module.exports = isProperFraction;
-
-// Here's our helper again
-function assertEquals(actualOutput, targetOutput) {
-  console.assert(
-    actualOutput === targetOutput,
-    `Expected ${actualOutput} to equal ${targetOutput}`
-  );
-}
-
-// TODO: Write tests to cover all cases.
-// What combinations of numerators and denominators should you test?
-
-// Example: 1/2 is a proper fraction
-assertEquals(isProperFraction(1, 2), true);
diff --git a/Sprint-3/1-implement-and-rewrite-tests/implement/3-get-card-value.js b/Sprint-3/1-implement-and-rewrite-tests/implement/3-get-card-value.js
index c7559e787e..b2b41807b9 100644
--- a/Sprint-3/1-implement-and-rewrite-tests/implement/3-get-card-value.js
+++ b/Sprint-3/1-implement-and-rewrite-tests/implement/3-get-card-value.js
@@ -1,52 +1,16 @@
-// This problem involves playing cards: https://en.wikipedia.org/wiki/Standard_52-card_deck
-
-// Implement a function getCardValue, when given a string representing a playing card,
-// should return the numerical value of the card.
-
-// A valid card string will contain a rank followed by the suit.
-// The rank can be one of the following strings:
-//   "A", "2", "3", "4", "5", "6", "7", "8", "9", "10", "J", "Q", "K"
-// The suit can be one of the following emojis:
-//   "♠", "♥", "♦", "♣"
-// For example: "A♠", "2♥", "10♥", "J♣", "Q♦", "K♦".
-
-// When the card is an ace ("A"), the function should return 11.
-// When the card is a face card ("J", "Q", "K"), the function should return 10.
-// When the card is a number card ("2" to "10"), the function should return its numeric value.
-
-// When the card string is invalid (not following the above format), the function should
-// throw an error.
-
-// Acceptance criteria:
-// After you have implemented the function, write tests to cover all the cases, and
-// execute the code to ensure all tests pass.
-
 function getCardValue(card) {
-  // TODO: Implement this function
+  const rank = card.slice(0, -1); // everything except the last char (suit)
+  const suit = card.slice(-1);     // last char (suit)
+  const validSuits = ["♠","♥","♦","♣"];
+  const validRanks = ["A","2","3","4","5","6","7","8","9","10","J","Q","K"];
+
+  if (!validRanks.includes(rank) || !validSuits.includes(suit)) {
+    throw new Error("Invalid card");
+  }
+
+  if (rank === "A") return 11;
+  if (["J","Q","K"].includes(rank)) return 10;
+  return Number(rank);
 }
 
-// The line below allows us to load the getCardValue function into tests in other files.
-// This will be useful in the "rewrite tests with jest" step.
 module.exports = getCardValue;
-
-// Helper functions to make our assertions easier to read.
-function assertEquals(actualOutput, targetOutput) {
-  console.assert(
-    actualOutput === targetOutput,
-    `Expected ${actualOutput} to equal ${targetOutput}`
-  );
-}
-
-// TODO: Write tests to cover all outcomes, including throwing errors for invalid cards.
-// Examples:
-assertEquals(getCardValue("9♠"), 9);
-
-// Handling invalid cards
-try {
-  getCardValue("invalid");
-
-  // This line will not be reached if an error is thrown as expected
-  console.error("Error was not thrown for invalid card");
-} catch (e) {}
-
-// What other invalid card cases can you think of?