diff --git a/implement-and-rewrite-tests/implement-tests-with-node-test/1-get-angle-type.test.js b/implement-and-rewrite-tests/implement-tests-with-node-test/1-get-angle-type.test.js
index cf50f6cad..7e223870a 100644
--- a/implement-and-rewrite-tests/implement-tests-with-node-test/1-get-angle-type.test.js
+++ b/implement-and-rewrite-tests/implement-tests-with-node-test/1-get-angle-type.test.js
@@ -3,10 +3,48 @@ import test from "node:test";
 
 import { getAngleType } from "../implement/1-get-angle-type.js";
 
-// TODO: Write tests to cover all cases, including boundary and invalid cases.
 // Example: Identify Right Angles
 
 test("Classifies right angles", () => {
   const right = getAngleType(90);
   assert.equal(right, "Right angle");
 });
+
+// Acute Angles (0° < angle < 90°)
+test("Classifies acute angles", () => {
+  assert.equal(getAngleType(1), "Acute angle");
+  assert.equal(getAngleType(45), "Acute angle");
+  assert.equal(getAngleType(89.9), "Acute angle");
+});
+
+// Right Angles (angle === 90°)
+test("Classifies right angles", () => {
+  assert.equal(getAngleType(90), "Right angle");
+});
+
+// Obtuse Angles (90° < angle < 180°)
+test("Classifies obtuse angles", () => {
+  assert.equal(getAngleType(90.1), "Obtuse angle");
+  assert.equal(getAngleType(135), "Obtuse angle");
+  assert.equal(getAngleType(179.9), "Obtuse angle");
+});
+
+// Straight Angles (angle === 180°)
+test("Classifies straight angles", () => {
+  assert.equal(getAngleType(180), "Straight angle");
+});
+
+// Reflex Angles (180° < angle < 360°)
+test("Classifies reflex angles", () => {
+  assert.equal(getAngleType(180.1), "Reflex angle");
+  assert.equal(getAngleType(270), "Reflex angle");
+  assert.equal(getAngleType(359.9), "Reflex angle");
+});
+
+// Invalid & Boundary Cases (<= 0° or >= 360°)
+test("Classifies invalid angles and exact boundaries", () => {
+  assert.equal(getAngleType(0), "Invalid angle");
+  assert.equal(getAngleType(-45), "Invalid angle");
+  assert.equal(getAngleType(360), "Invalid angle");
+  assert.equal(getAngleType(400), "Invalid angle");
+});
diff --git a/implement-and-rewrite-tests/implement-tests-with-node-test/2-is-proper-fraction.test.js b/implement-and-rewrite-tests/implement-tests-with-node-test/2-is-proper-fraction.test.js
index a29084605..d821ad498 100644
--- a/implement-and-rewrite-tests/implement-tests-with-node-test/2-is-proper-fraction.test.js
+++ b/implement-and-rewrite-tests/implement-tests-with-node-test/2-is-proper-fraction.test.js
@@ -6,7 +6,33 @@ import { isProperFraction } from "../implement/2-is-proper-fraction.js";
 // TODO: Write tests to cover all cases.
 // What combinations of numerators and denominators should you test?
 
+
 test("Basic proper fraction", () => {
   // Example: 1/2 is a proper fraction
   assert.equal(isProperFraction(1, 2), true);
+  assert.equal(isProperFraction(3, 4), true);
+});
+
+test("Improper fraction where numerator is larger than denominator", () => {
+  assert.equal(isProperFraction(5, 2), false);
+  assert.equal(isProperFraction(4, 3), false);
+});
+
+test("Equal numerator and denominator (equals 1)", () => {
+  assert.equal(isProperFraction(3, 3), false);
 });
+
+test("Denominator is zero", () => {
+  assert.equal(isProperFraction(1, 0), false);
+  assert.equal(isProperFraction(0, 0), false);
+});
+
+test("Zero numerator with non-zero denominator", () => {
+  assert.equal(isProperFraction(0, 5), true);
+});
+
+test("Negative numbers", () => {
+  assert.equal(isProperFraction(-1, 2), true);
+  assert.equal(isProperFraction(1, -2), true);
+  assert.equal(isProperFraction(-3, -2), false);
+});
\ No newline at end of file
diff --git a/implement-and-rewrite-tests/implement-tests-with-node-test/3-get-card-value.test.js b/implement-and-rewrite-tests/implement-tests-with-node-test/3-get-card-value.test.js
index f5092d9b1..f590aac82 100644
--- a/implement-and-rewrite-tests/implement-tests-with-node-test/3-get-card-value.test.js
+++ b/implement-and-rewrite-tests/implement-tests-with-node-test/3-get-card-value.test.js
@@ -5,12 +5,73 @@ import { getCardValue } from "../implement/3-get-card-value.js";
 
 // TODO: Write tests to cover all outcomes, including throwing errors for invalid cards.
 
-test("Valid single-digit card", () => {
-  assert.equal(getCardValue("9♠"), 9);
+test("Valid single-digit number cards return correct values", () => {
+  assert.equal(getCardValue("2♠"), 2);
+  assert.equal(getCardValue("5♥"), 5);
+  assert.equal(getCardValue("9♦"), 9);
 });
 
-test("Arbitrary non-card string", () => {
-  assert.throws(() => getCardValue("invalid"), /Expected a number followed by a suit, but got "invalid"/, "Expected clear error");
+test("Valid double-digit card (10) returns 10", () => {
+  assert.equal(getCardValue("10♥"), 10);
+  assert.equal(getCardValue("10♣"), 10);
 });
 
-// TODO: What other invalid card cases can you think of?
+test("Ace cards return 11", () => {
+  assert.equal(getCardValue("A♠"), 11);
+  assert.equal(getCardValue("A♦"), 11);
+});
+
+test("Face cards (J, Q, K) return 10", () => {
+  assert.equal(getCardValue("J♣"), 10);
+  assert.equal(getCardValue("Q♦"), 10);
+  assert.equal(getCardValue("K♠"), 10);
+});
+
+// Invalid Input Cases
+test("Throws error for arbitrary non-card string", () => {
+  assert.throws(
+    () => getCardValue("invalid"),
+    /Expected a card rank followed by a suit/
+  );
+});
+
+test("Throws error for invalid ranks or suit-like characters", () => {
+  assert.throws(
+    () => getCardValue("1♠"),
+    /Expected a card rank followed by a suit/
+  );
+  assert.throws(
+    () => getCardValue("11♥"),
+    /Expected a card rank followed by a suit/
+  );
+  assert.throws(
+    () => getCardValue("Z♠"),
+    /Expected a card rank followed by a suit/
+  );
+});
+
+test("Throws error for invalid or missing suit", () => {
+  assert.throws(
+    () => getCardValue("10"),
+    /Expected a card rank followed by a suit/
+  );
+  assert.throws(
+    () => getCardValue("AX"),
+    /Expected a card rank followed by a suit/
+  );
+});
+
+test("Throws error for reversed order (suit before rank)", () => {
+  assert.throws(
+    () => getCardValue("♠A"),
+    /Expected a card rank followed by a suit/
+  );
+});
+
+test("Throws error for empty string or non-string input", () => {
+  assert.throws(
+    () => getCardValue(""),
+    /Expected a card rank followed by a suit/
+  );
+  assert.throws(() => getCardValue(10), /Expected a string/);
+});
diff --git a/implement-and-rewrite-tests/implement/1-get-angle-type.js b/implement-and-rewrite-tests/implement/1-get-angle-type.js
index 8a6fba050..00df61114 100644
--- a/implement-and-rewrite-tests/implement/1-get-angle-type.js
+++ b/implement-and-rewrite-tests/implement/1-get-angle-type.js
@@ -17,5 +17,21 @@
 // execute the code to ensure all tests pass.
 
 export function getAngleType(angle) {
-  // TODO: Implement this function
+  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";
+  }
+
+  return "Invalid angle";
 }
diff --git a/implement-and-rewrite-tests/implement/2-is-proper-fraction.js b/implement-and-rewrite-tests/implement/2-is-proper-fraction.js
index f983800f0..376a2cbc0 100644
--- a/implement-and-rewrite-tests/implement/2-is-proper-fraction.js
+++ b/implement-and-rewrite-tests/implement/2-is-proper-fraction.js
@@ -14,5 +14,9 @@
 // execute the code to ensure all tests pass.
 
 export function isProperFraction(numerator, denominator) {
-  // TODO: Implement this function
+  if (denominator === 0) {
+    return false;
+  }
+
+  return Math.abs(numerator) < Math.abs(denominator);
 }
diff --git a/implement-and-rewrite-tests/implement/3-get-card-value.js b/implement-and-rewrite-tests/implement/3-get-card-value.js
index 9614ab1ee..b929b5bb3 100644
--- a/implement-and-rewrite-tests/implement/3-get-card-value.js
+++ b/implement-and-rewrite-tests/implement/3-get-card-value.js
@@ -24,5 +24,28 @@
 // execute the code to ensure all tests pass.
 
 export function getCardValue(card) {
-  // TODO: Implement this function
+  if (typeof card !== "string") {
+    throw new Error(`Expected a string, but got ${typeof card}`);
+  }
+
+  const cardRegex = /^(10|[2-9]|[AJQK])([♠♥♦♣])$/;
+  const match = card.match(cardRegex);
+
+  if (!match) {
+    throw new Error(
+      `Expected a card rank followed by a suit, but got "${card}"`
+    );
+  }
+
+  const rank = match[1];
+
+  if (rank === "A") {
+    return 11;
+  }
+
+  if (["J", "Q", "K"].includes(rank)) {
+    return 10;
+  }
+
+  return Number(rank);
 }
diff --git a/implement-and-rewrite-tests/rewrite-tests-with-jest/1-get-angle-type.test.js b/implement-and-rewrite-tests/rewrite-tests-with-jest/1-get-angle-type.test.js
index e0ba786ab..32dc72a58 100644
--- a/implement-and-rewrite-tests/rewrite-tests-with-jest/1-get-angle-type.test.js
+++ b/implement-and-rewrite-tests/rewrite-tests-with-jest/1-get-angle-type.test.js
@@ -3,16 +3,43 @@ import { getAngleType } from "../implement/1-get-angle-type.js";
 // TODO: Write tests in Jest syntax to cover all cases/outcomes,
 // including boundary and invalid cases.
 
+
 // Case 1: Acute angles
 test(`should return "Acute angle" when (0 < angle < 90)`, () => {
   // Test various acute angles, including boundary cases
   expect(getAngleType(1)).toEqual("Acute angle");
   expect(getAngleType(45)).toEqual("Acute angle");
-  expect(getAngleType(89)).toEqual("Acute angle");
+  expect(getAngleType(89.9)).toEqual("Acute angle");
 });
 
 // Case 2: Right angle
+test(`should return "Right angle" when angle is exactly 90`, () => {
+  expect(getAngleType(90)).toEqual("Right angle");
+});
+
 // Case 3: Obtuse angles
+test(`should return "Obtuse angle" when (90 < angle < 180)`, () => {
+  expect(getAngleType(90.1)).toEqual("Obtuse angle");
+  expect(getAngleType(135)).toEqual("Obtuse angle");
+  expect(getAngleType(179.9)).toEqual("Obtuse angle");
+});
+
 // Case 4: Straight angle
+test(`should return "Straight angle" when angle is exactly 180`, () => {
+  expect(getAngleType(180)).toEqual("Straight angle");
+});
+
 // Case 5: Reflex angles
+test(`should return "Reflex angle" when (180 < angle < 360)`, () => {
+  expect(getAngleType(180.1)).toEqual("Reflex angle");
+  expect(getAngleType(270)).toEqual("Reflex angle");
+  expect(getAngleType(359.9)).toEqual("Reflex angle");
+});
+
 // Case 6: Invalid angles
+test(`should return "Invalid angle" when angle is <= 0 or >= 360`, () => {
+  expect(getAngleType(0)).toEqual("Invalid angle");
+  expect(getAngleType(-45)).toEqual("Invalid angle");
+  expect(getAngleType(360)).toEqual("Invalid angle");
+  expect(getAngleType(400)).toEqual("Invalid angle");
+});
\ No newline at end of file
diff --git a/implement-and-rewrite-tests/rewrite-tests-with-jest/2-is-proper-fraction.test.js b/implement-and-rewrite-tests/rewrite-tests-with-jest/2-is-proper-fraction.test.js
index 5d49e2d8b..3ef0e69f5 100644
--- a/implement-and-rewrite-tests/rewrite-tests-with-jest/2-is-proper-fraction.test.js
+++ b/implement-and-rewrite-tests/rewrite-tests-with-jest/2-is-proper-fraction.test.js
@@ -2,7 +2,38 @@ import { isProperFraction } from "../implement/2-is-proper-fraction.js";
 
 // TODO: Write tests in Jest syntax to cover all combinations of positives, negatives, zeros, and other categories.
 
+// Positive numbers
+test("should return true when positive numerator is less than positive denominator", () => {
+  expect(isProperFraction(1, 2)).toEqual(true);
+  expect(isProperFraction(3, 4)).toEqual(true);
+});
+
+test("should return false when positive numerator is equal to or greater than positive denominator", () => {
+  expect(isProperFraction(3, 3)).toEqual(false);
+  expect(isProperFraction(5, 2)).toEqual(false);
+});
+
 // Special case: numerator is zero
-test(`should return false when denominator is zero`, () => {
+
+test("should return false when denominator is zero", () => {
   expect(isProperFraction(1, 0)).toEqual(false);
+  expect(isProperFraction(0, 0)).toEqual(false);
+});
+
+test("should return true when numerator is zero and denominator is non-zero", () => {
+  expect(isProperFraction(0, 5)).toEqual(true);
+  expect(isProperFraction(0, -5)).toEqual(true);
+});
+
+// Negative numbers
+test("should return true when absolute value of numerator is less than denominator", () => {
+  expect(isProperFraction(-1, 2)).toEqual(true);
+  expect(isProperFraction(1, -2)).toEqual(true);
+  expect(isProperFraction(-1, -2)).toEqual(true);
+});
+
+test("should return false when absolute value of numerator is equal to or greater than denominator", () => {
+  expect(isProperFraction(-5, 2)).toEqual(false);
+  expect(isProperFraction(5, -2)).toEqual(false);
+  expect(isProperFraction(-3, -3)).toEqual(false);
 });
diff --git a/implement-and-rewrite-tests/rewrite-tests-with-jest/3-get-card-value.test.js b/implement-and-rewrite-tests/rewrite-tests-with-jest/3-get-card-value.test.js
index a6de5a82a..74a8b581d 100644
--- a/implement-and-rewrite-tests/rewrite-tests-with-jest/3-get-card-value.test.js
+++ b/implement-and-rewrite-tests/rewrite-tests-with-jest/3-get-card-value.test.js
@@ -2,17 +2,57 @@ import { getCardValue } from "../implement/3-get-card-value.js";
 
 // TODO: Write tests in Jest syntax to cover all possible outcomes.
 
+
 // Case 1: Ace (A)
-test(`Should return 11 when given an ace card`, () => {
+test("Should return 11 when given an ace card", () => {
   expect(getCardValue("A♠")).toEqual(11);
+  expect(getCardValue("A♦")).toEqual(11);
 });
 
-// Suggestion: Group the remaining test data into these categories:
-//   Number Cards (2-10)
-//   Face Cards (J, Q, K)
-//   Invalid Cards
+// Case 2: Number Cards (2-10)
+test("Should return numeric value for single-digit number cards", () => {
+  expect(getCardValue("2♠")).toEqual(2);
+  expect(getCardValue("5♥")).toEqual(5);
+  expect(getCardValue("9♦")).toEqual(9);
+});
+
+test("Should return 10 for '10' cards across all suits", () => {
+  expect(getCardValue("10♥")).toEqual(10);
+  expect(getCardValue("10♣")).toEqual(10);
+});
+
+// Case 3: Face Cards (J, Q, K)
+test("Should return 10 for face cards (J, Q, K)", () => {
+  expect(getCardValue("J♣")).toEqual(10);
+  expect(getCardValue("Q♦")).toEqual(10);
+  expect(getCardValue("K♠")).toEqual(10);
+});
+
+// Case 4: Invalid Cards
+test("Should throw an error for arbitrary non-card strings", () => {
+  expect(() => getCardValue("invalid")).toThrow();
+});
+
+test("Should throw an error for invalid ranks or suit-like characters", () => {
+  expect(() => getCardValue("1♠")).toThrow();
+  expect(() => getCardValue("11♥")).toThrow();
+  expect(() => getCardValue("Z♠")).toThrow();
+});
+
+test("Should throw an error for missing or invalid suit", () => {
+  expect(() => getCardValue("10")).toThrow();
+  expect(() => getCardValue("AX")).toThrow();
+});
+
+test("Should throw an error when suit is before rank", () => {
+  expect(() => getCardValue("♠A")).toThrow();
+});
+
+test("Should throw an error for non-string or empty inputs", () => {
+  expect(() => getCardValue("")).toThrow();
+  expect(() => getCardValue(10)).toThrow();
+});
 
 // To learn how to test whether a function throws an error as expected in Jest,
 // please refer to the Jest documentation:
 // https://jestjs.io/docs/expect#tothrowerror
-
diff --git a/test-driven-development/fizzbuzz.js b/test-driven-development/fizzbuzz.js
new file mode 100644
index 000000000..12198b29f
--- /dev/null
+++ b/test-driven-development/fizzbuzz.js
@@ -0,0 +1,10 @@
+function fizzbuzz(number){
+  if (number % 3 === 0 && number % 5 === 0){
+    return "fizzbuzz";
+  } else if (number % 5 === 0){
+    return "buzz";
+  } else if (number % 3 === 0){
+    return "fizz";
+  }
+  return number.toString();
+};
\ No newline at end of file
diff --git a/test-driven-development/fizzbuzz.test.js b/test-driven-development/fizzbuzz.test.js
new file mode 100644
index 000000000..e48f23149
--- /dev/null
+++ b/test-driven-development/fizzbuzz.test.js
@@ -0,0 +1,36 @@
+import {fizzbuzz} from './fizzbuzz.js';
+import assert from 'node:assert';
+import {test, describe} from 'node:test';
+
+describe('division by 3 and 5', () => { 
+
+    test('15 returns fizzbuzz', () => {
+        assert.equal(fizzbuzz(15), "fizzbuzz");
+    });
+
+    test('30 returns fizzbuzz', () => {
+        assert.equal(fizzbuzz(30), "fizzbuzz");
+    });
+
+    test('90 returns fizzbuzz', () => {
+        assert.equal(fizzbuzz(90), "fizzbuzz");
+    });
+
+});
+
+
+describe('returning the number as a string', () => { 
+
+    test('1 returns "1"', () => {
+        assert.equal(fizzbuzz(1), "1");
+    });
+
+    test('4 returns "4"', () => {
+        assert.equal(fizzbuzz(4), "4");
+    });
+
+    test('91 returns "91"', () => {
+        assert.equal(fizzbuzz(91), "91");
+    });
+
+});
\ No newline at end of file