diff --git a/challenges/challenge-cowsay-two/solution1.js b/challenges/challenge-cowsay-two/solution1.js
index a7f2416b..616e6b2d 100644
--- a/challenges/challenge-cowsay-two/solution1.js
+++ b/challenges/challenge-cowsay-two/solution1.js
@@ -1,30 +1,35 @@
-// =================
-// Stripped down cowsayer CLI, 
-// no libraries
-// https://nodejs.dev/learn/nodejs-accept-arguments-from-the-command-line
-// =================
+// cowsay.js
 
 // 1. Accept arguments
+const userInput = process.argv.slice(2).join(' ');
+
+// 2. Make speech bubble
+function makeBubble(text) {
+    if (!text) text = "Moo!";
+    const len = text.length;
+    const top = ' ' + '_'.repeat(len + 2);
+    const middle = `| ${text} |`;
+    const bottom = ' ' + '-'.repeat(len + 2);
+    return `${top}\n${middle}\n${bottom}`;
+}
 
-// how will you accept arguments?
-
-// 2. Make supplies for our speech bubble
-
-let topLine = '_';
-let bottomLine = '-';
-let saying = '';
-
-// 3. Make a cow that takes a string
+// 3. Make a simple cow
+function makeCow() {
+    return `
+        \\   ^__^
+         \\  (oo)\\_______
+            (__)\\       )\\/\\
+                ||----w |
+                ||     ||
+    `;
+}
 
+// 4. Combine bubble + cow
 function cowsay(saying) {
-// how will you make the speech bubble contain the text?
-
-// where will the cow picture go?
-
-// how will you account for the parameter being empty?
-
+    const bubble = makeBubble(saying);
+    const cow = makeCow();
+    return bubble + cow;
 }
 
-//4. Pipe argument into cowsay function and return a cow
-
-// how will you log this to the console?
+// 5. Log to console
+console.log(cowsay(userInput));
diff --git a/challenges/challenge-cowsay-two/solution2.js b/challenges/challenge-cowsay-two/solution2.js
index 8aca8572..cec709da 100644
--- a/challenges/challenge-cowsay-two/solution2.js
+++ b/challenges/challenge-cowsay-two/solution2.js
@@ -1,18 +1,32 @@
-// =================
-// Stripped down cowsayer CLI, 
-// no libraries or arguments
-// https://nodejs.dev/learn/accept-input-from-the-command-line-in-nodejs
-// =================
+const readline = require('readline');
 
-// 1. Make  a command line interface.
+const rl = readline.createInterface({
+    input: process.stdin,
+    output: process.stdout
+});
 
-// 2. Make supplies for our speech bubble
-
-// 3. Make a cow that takes a string
+function makeBubble(text) {
+    if (!text) text = "Moo!";
+    const len = text.length;
+    const top = ' ' + '_'.repeat(len + 2);
+    const middle = `| ${text} |`;
+    const bottom = ' ' + '-'.repeat(len + 2);
+    return `${top}\n${middle}\n${bottom}`;
+}
 
 const cow = (saying) => {
-    // how did you make the cow before?
-}
+    const bubble = makeBubble(saying);
+    const asciiCow = `
+        \\   ^__^
+         \\  (oo)\\_______
+            (__)\\       )\\/\\
+                ||----w |
+                ||     ||
+    `;
+    return bubble + asciiCow;
+};
 
-// 4. Use readline to get a string from the terminal 
-// (with a prompt so it's clearer what we want)
\ No newline at end of file
+rl.question("What should the cow say? ", (answer) => {
+    console.log(cow(answer));
+    rl.close();
+});
diff --git a/challenges/challenge-weather-app/app.js b/challenges/challenge-weather-app/app.js
new file mode 100644
index 00000000..3c0cda9c
--- /dev/null
+++ b/challenges/challenge-weather-app/app.js
@@ -0,0 +1,97 @@
+// ====================
+// Mini-weather App JS
+// ====================
+
+// Your working API keys
+const WEATHER_API_KEY = "13940029dbb0ac27fa8e76f770798f71"; 
+const UNSPLASH_ACCESS_KEY = "1EkJLQ64exkT3BxWkvtunY6nGsyoUpmmVOIycUfobC4";
+
+// DOM elements
+const photoEl = document.getElementById("photo");
+const thumbsEl = document.getElementById("thumbs");
+const conditionsEl = document.getElementById("conditions");
+const creditUserEl = document.getElementById("credit-user");
+const searchForm = document.getElementById("search");
+const searchInput = document.getElementById("search-tf");
+
+// Fetch weather data from OpenWeather
+async function getWeather(city = "London") {
+    const url = `https://api.openweathermap.org/data/2.5/weather?q=${city}&appid=${WEATHER_API_KEY}&units=metric`;
+    const res = await fetch(url);
+    if (!res.ok) throw new Error("Invalid API key or city");
+    const data = await res.json();
+    return data;
+}
+
+// Fetch images from Unsplash
+async function getImages(query) {
+    const url = `https://api.unsplash.com/search/photos?query=${query}&client_id=${UNSPLASH_ACCESS_KEY}&per_page=5`;
+    const res = await fetch(url);
+    const data = await res.json();
+    return data.results;
+}
+
+// Display main photo and thumbnails
+function displayImages(images) {
+    if (!images.length) return;
+
+    const mainImage = images[0];
+    photoEl.style.backgroundImage = `url(${mainImage.urls.regular})`;
+    creditUserEl.textContent = mainImage.user.name;
+    creditUserEl.href = mainImage.user.links.html;
+
+    thumbsEl.innerHTML = "";
+
+    images.forEach((img, index) => {
+        const thumb = document.createElement("div");
+        thumb.classList.add("thumb");
+        if (index === 0) thumb.classList.add("active");
+        thumb.style.backgroundImage = `url(${img.urls.thumb})`;
+        thumb.dataset.full = img.urls.regular;
+        thumb.dataset.userName = img.user.name;
+        thumb.dataset.userLink = img.user.links.html;
+
+        thumb.addEventListener("click", () => {
+            photoEl.style.backgroundImage = `url(${img.urls.regular})`;
+            creditUserEl.textContent = img.user.name;
+            creditUserEl.href = img.user.links.html;
+
+            document.querySelectorAll(".thumb").forEach(t => t.classList.remove("active"));
+            thumb.classList.add("active");
+        });
+
+        thumbsEl.appendChild(thumb);
+    });
+}
+
+// Display weather info
+function displayWeather(weatherData) {
+    const description = weatherData.weather[0].description;
+    const temp = Math.round(weatherData.main.temp);
+    const cityName = weatherData.name;
+    conditionsEl.textContent = `${description}, ${temp}°C in ${cityName}`;
+}
+
+// Update city
+async function updateCity(city) {
+    try {
+        const weather = await getWeather(city);
+        displayWeather(weather);
+        const images = await getImages(weather.weather[0].description);
+        displayImages(images);
+    } catch (err) {
+        console.error(err);
+        conditionsEl.textContent = "Error fetching weather or images!";
+    }
+}
+
+// Load default city
+updateCity("London");
+
+// Handle search form
+searchForm.addEventListener("submit", (e) => {
+    e.preventDefault();
+    const city = searchInput.value.trim();
+    if (city) updateCity(city);
+    searchInput.value = "";
+});
diff --git a/challenges/challenge-weather-app/index.html b/challenges/challenge-weather-app/index.html
index b1add346..f25d1058 100644
--- a/challenges/challenge-weather-app/index.html
+++ b/challenges/challenge-weather-app/index.html
@@ -44,6 +44,7 @@ <h1 class="title">
   </main>
 
   <!-- JS goes here -->
+   <script src="app.js"></script>
 </body>
 
 </html>
diff --git a/challenges/dog-photo-gallery/index.html b/challenges/dog-photo-gallery/index.html
new file mode 100644
index 00000000..b8051e15
--- /dev/null
+++ b/challenges/dog-photo-gallery/index.html
@@ -0,0 +1,17 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+  <meta charset="UTF-8">
+  <meta name="viewport" content="width=device-width, initial-scale=1.0">
+  <title>Dog Photo Gallery</title>
+    <link rel="stylesheet" href="styles.css">
+</head>
+<body>
+  <h1>🐕 Random Dog Photo Gallery</h1>
+  <button id="add-dog">Add Dog</button>
+  <button id="clear-gallery">Clear Gallery</button>
+  <ul id="dog-gallery"></ul>
+
+  <script src="script.js"></script>
+</body>
+</html>
diff --git a/challenges/dog-photo-gallery/script.js b/challenges/dog-photo-gallery/script.js
new file mode 100644
index 00000000..2585f0bf
--- /dev/null
+++ b/challenges/dog-photo-gallery/script.js
@@ -0,0 +1,33 @@
+const addDogBtn = document.getElementById("add-dog");
+const clearGalleryBtn = document.getElementById("clear-gallery");
+const gallery = document.getElementById("dog-gallery");
+
+async function fetchDogImage() {
+  try {
+    const response = await fetch("https://dog.ceo/api/breeds/image/random");
+    if (!response.ok) {
+      throw new Error(`HTTP error! Status: ${response.status}`);
+    }
+    const data = await response.json();
+
+    // Create elements
+    const li = document.createElement("li");
+    const img = document.createElement("img");
+    img.src = data.message;
+    img.alt = "Cute Dog";
+
+    // Append to list
+    li.appendChild(img);
+    gallery.appendChild(li);
+
+  } catch (error) {
+    console.error("Error fetching dog image:", error);
+    alert("🐶 Oops! Failed to fetch a dog image. Try again.");
+  }
+}
+
+// Event listeners
+addDogBtn.addEventListener("click", fetchDogImage);
+clearGalleryBtn.addEventListener("click", () => {
+  gallery.innerHTML = "";
+});
diff --git a/challenges/dog-photo-gallery/style.css b/challenges/dog-photo-gallery/style.css
new file mode 100644
index 00000000..180dd371
--- /dev/null
+++ b/challenges/dog-photo-gallery/style.css
@@ -0,0 +1,38 @@
+body {
+      font-family: Arial, sans-serif;
+      text-align: center;
+      padding: 20px;
+  }
+
+  button {
+      margin: 10px;
+      padding: 10px 20px;
+      cursor: pointer;
+      border-radius: 8px;
+      border: none;
+      background: #4CAF50;
+      color: white;
+      font-size: 16px;
+  }
+
+  button:hover {
+      background: #45a049;
+  }
+
+  ul {
+      list-style: none;
+      padding: 0;
+      display: flex;
+      flex-wrap: wrap;
+      justify-content: center;
+  }
+
+  li {
+      margin: 10px;
+  }
+
+  img {
+      max-width: 200px;
+      border-radius: 12px;
+      box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
+  }
\ No newline at end of file
diff --git a/challenges/unit-testing/katas-tdd/calculator/calculator.js b/challenges/unit-testing/katas-tdd/calculator/calculator.js
new file mode 100644
index 00000000..b95ed43e
--- /dev/null
+++ b/challenges/unit-testing/katas-tdd/calculator/calculator.js
@@ -0,0 +1,14 @@
+export function add(numbers) {
+  if (numbers === "") return 0;
+
+  const parts = numbers.split(",").map(Number);
+  const negatives = parts.filter((num) => num < 0);
+
+  if (negatives.length > 0) {
+    throw new Error(`negatives not allowed: ${negatives.join(",")}`);
+  }
+
+  return parts
+    .filter((num) => num <= 1000) // ignore > 1000
+    .reduce((sum, num) => sum + num, 0);
+}
\ No newline at end of file
diff --git a/challenges/unit-testing/katas-tdd/calculator/calculator.test.js b/challenges/unit-testing/katas-tdd/calculator/calculator.test.js
new file mode 100644
index 00000000..e1af88ad
--- /dev/null
+++ b/challenges/unit-testing/katas-tdd/calculator/calculator.test.js
@@ -0,0 +1,15 @@
+import { add } from "./calculator";
+
+describe("Calculator", () => {
+  test("should return 0 for empty string", () => {
+    expect(add("")).toBe(0);
+  });
+
+  test("should return the number itself when only one number is given", () => {
+    expect(add("5")).toBe(5);
+  });
+
+  test("should return sum of two numbers", () => {
+    expect(add("3,6")).toBe(9);
+  });
+});
diff --git a/challenges/unit-testing/katas-tdd/password-verifier/verify.js b/challenges/unit-testing/katas-tdd/password-verifier/verify.js
new file mode 100644
index 00000000..54cdaba0
--- /dev/null
+++ b/challenges/unit-testing/katas-tdd/password-verifier/verify.js
@@ -0,0 +1,15 @@
+export function verify(password) {
+  if (!password || password.length < 8) {
+    return "Password rejected";
+  }
+
+  if (!/[A-Z]/.test(password)) {
+    return "Password rejected";
+  }
+
+  if (!/[0-9]/.test(password)) {
+    return "Password rejected";
+  }
+
+  return "Password accepted";
+}
diff --git a/challenges/unit-testing/katas-tdd/password-verifier/verify.test.js b/challenges/unit-testing/katas-tdd/password-verifier/verify.test.js
new file mode 100644
index 00000000..9af6a931
--- /dev/null
+++ b/challenges/unit-testing/katas-tdd/password-verifier/verify.test.js
@@ -0,0 +1,25 @@
+import { verify } from "./verify.js";
+
+describe("Password Verifier", () => {
+
+  test("rejects password shorter than 8 characters", () => {
+    expect(verify("Ab1")).toBe("Password rejected");
+  });
+
+  test("rejects null password", () => {
+    expect(verify(null)).toBe("Password rejected");
+  });
+
+  test("rejects password without uppercase letter", () => {
+    expect(verify("password1")).toBe("Password rejected");
+  });
+
+  test("rejects password without number", () => {
+    expect(verify("Password")).toBe("Password rejected");
+  });
+
+  test("accepts valid password", () => {
+    expect(verify("Password1")).toBe("Password accepted");
+  });
+
+});
diff --git a/challenges/unit-testing/katas-tdd/roman-numerals/convert-to-new-roman.js b/challenges/unit-testing/katas-tdd/roman-numerals/convert-to-new-roman.js
index 0f2fe4b5..ec338ce3 100644
--- a/challenges/unit-testing/katas-tdd/roman-numerals/convert-to-new-roman.js
+++ b/challenges/unit-testing/katas-tdd/roman-numerals/convert-to-new-roman.js
@@ -1,3 +1,20 @@
-function convertToNewRoman(n) {}
+function convertToNewRoman(n) {
+  // Step 1: simple mapping for 1–10 as example
+  const romanNumerals = {
+    1: "I",
+    2: "II",
+    3: "III",
+    4: "IV",
+    5: "V",
+    6: "VI",
+    7: "VII",
+    8: "VIII",
+    9: "IX",
+    10: "X",
+  };
+
+  return romanNumerals[n] || "";
+}
 
 module.exports = convertToNewRoman;
+
diff --git a/challenges/unit-testing/katas-tdd/roman-numerals/convert-to-new-roman.test.js b/challenges/unit-testing/katas-tdd/roman-numerals/convert-to-new-roman.test.js
index ae49f737..2d6c2c00 100644
--- a/challenges/unit-testing/katas-tdd/roman-numerals/convert-to-new-roman.test.js
+++ b/challenges/unit-testing/katas-tdd/roman-numerals/convert-to-new-roman.test.js
@@ -1,7 +1,25 @@
-let convertToNewRoman = require("./convert-to-new-roman");
+const convertToNewRoman = require("convert-to-new-roman.js");
 
-test("returns I if passed 1 as an argument", function () {
+test("returns I if passed 1 as an argument", () => {
   // Arrange
+  const input = 1;
+
   // Act
+  const result = convertToNewRoman(input);
+
   // Assert
+  expect(result).toBe("I");
+});
+
+test("returns V if passed 5 as an argument", () => {
+  const input = 5;
+  const result = convertToNewRoman(input);
+  expect(result).toBe("V");
 });
+
+test("returns X if passed 10 as an argument", () => {
+  const input = 10;
+  const result = convertToNewRoman(input);
+  expect(result).toBe("X");
+});
+
diff --git a/challenges/unit-testing/katas-tdd/roman-numerals/convert-to-old-roman.js b/challenges/unit-testing/katas-tdd/roman-numerals/convert-to-old-roman.js
index f7f0d06d..866d64c2 100644
--- a/challenges/unit-testing/katas-tdd/roman-numerals/convert-to-old-roman.js
+++ b/challenges/unit-testing/katas-tdd/roman-numerals/convert-to-old-roman.js
@@ -1,3 +1,20 @@
-function convertToOldRoman(n) {}
+function convertToOldRoman(n) {
+  // Step 1: simple mapping for 1–10
+  const oldRomanNumerals = {
+    1: "I",
+    2: "II",
+    3: "III",
+    4: "IIII",
+    5: "V",
+    6: "VI",
+    7: "VII",
+    8: "VIII",
+    9: "VIIII",
+    10: "X",
+  };
+
+  return oldRomanNumerals[n] || "";
+}
 
 module.exports = convertToOldRoman;
+
diff --git a/challenges/unit-testing/katas-tdd/roman-numerals/convert-to-old-roman.test.js b/challenges/unit-testing/katas-tdd/roman-numerals/convert-to-old-roman.test.js
index b9a43869..dcaa8c6a 100644
--- a/challenges/unit-testing/katas-tdd/roman-numerals/convert-to-old-roman.test.js
+++ b/challenges/unit-testing/katas-tdd/roman-numerals/convert-to-old-roman.test.js
@@ -1,7 +1,22 @@
-let convertToOldRoman = require("./convert-to-old-roman");
+const convertToOldRoman = require("convert-to-old-roman.js");
 
-test("returns I if passed 1 as an argument", function () {
-  // Arrange
-  // Act
-  // Assert
+test("returns I if passed 1 as an argument", () => {
+  expect(convertToOldRoman(1)).toBe("I");
 });
+
+test("returns IIII if passed 4 as an argument", () => {
+  expect(convertToOldRoman(4)).toBe("IIII");
+});
+
+test("returns V if passed 5 as an argument", () => {
+  expect(convertToOldRoman(5)).toBe("V");
+});
+
+test("returns VIII if passed 8 as an argument", () => {
+  expect(convertToOldRoman(8)).toBe("VIII");
+});
+
+test("returns X if passed 10 as an argument", () => {
+  expect(convertToOldRoman(10)).toBe("X");
+});
+
diff --git a/challenges/unit-testing/passing-tests/car-sales/car-sales.js b/challenges/unit-testing/passing-tests/car-sales/car-sales.js
index e8bb8511..ccbce1b1 100644
--- a/challenges/unit-testing/passing-tests/car-sales/car-sales.js
+++ b/challenges/unit-testing/passing-tests/car-sales/car-sales.js
@@ -1,3 +1,20 @@
-function sales(carsSold) {}
+
+function sales(carsSold) {
+  const totals = {};
+
+  for (const car of carsSold) {
+    const make = car.make;
+    const price = car.price;
+
+    if (!totals[make]) {
+      totals[make] = 0;
+    }
+
+    totals[make] += price;
+  }
+
+  return totals; 
+}
 
 module.exports = sales;
+
diff --git a/challenges/unit-testing/passing-tests/car-sales/car-sales.test.js b/challenges/unit-testing/passing-tests/car-sales/car-sales.test.js
index 07139fc0..9f4b3233 100644
--- a/challenges/unit-testing/passing-tests/car-sales/car-sales.test.js
+++ b/challenges/unit-testing/passing-tests/car-sales/car-sales.test.js
@@ -1,7 +1,7 @@
-let sales = require("./car-sales");
+const sales = require("./car-sales");
 
-test("Car sales", function () {
-  let carsSold = [
+test("Car sales", () => {
+  const carsSold = [
     { make: "Ford", model: "Fiesta", colour: "Red", price: 5999 },
     { make: "Land Rover", model: "Defender", colour: "Muddy", price: 12000 },
     { make: "Toyota", model: "Prius", colour: "Silver", price: 6500 },
@@ -11,14 +11,14 @@ test("Car sales", function () {
     { make: "Ford", model: "Fiesta", colour: "Green", price: 2000 },
   ];
 
-  let totals = {
+  const totals = {
     Ford: 22999,
     Honda: 8000,
     "Land Rover": 21000,
     Toyota: 6500,
   };
 
-  let output = sales(carsSold);
+  const output = sales(carsSold);
 
   expect(output).toEqual(totals);
 });
diff --git a/challenges/unit-testing/passing-tests/factorial/factorial.js b/challenges/unit-testing/passing-tests/factorial/factorial.js
index fefa4368..17d74abc 100644
--- a/challenges/unit-testing/passing-tests/factorial/factorial.js
+++ b/challenges/unit-testing/passing-tests/factorial/factorial.js
@@ -1,13 +1,14 @@
-// int is an integer
-// a factorial is the product of all non-negative integers
-// less than or equal to the iniital number.
+function factorial(int) {
+  if (int === 0) return 1;
 
-// for example the factorial of 5 is 120
-// 120 = 1 * 2 * 3 * 4 * 5
+  let result = 1;
+  for (let i = 1; i <= int; i++) {
+    result *= i;
+  }
 
-// calculate and return the factorial of int
-// note: factorial of 0 is 1
-
-function factorial(int) {}
+  return result; 
+}
 
 module.exports = factorial;
+
+
diff --git a/challenges/unit-testing/passing-tests/get-average/get-average.js b/challenges/unit-testing/passing-tests/get-average/get-average.js
index b5588a57..2a2bb9e3 100644
--- a/challenges/unit-testing/passing-tests/get-average/get-average.js
+++ b/challenges/unit-testing/passing-tests/get-average/get-average.js
@@ -1,7 +1,13 @@
-// the input is an array of numbers and strings
-// return the average of all the numbers
-// be sure to exclude the strings
+function average(numbers) {
+  const numsOnly = numbers.filter(n => typeof n === "number");
 
-function average(numbers) {}
+  if (numsOnly.length === 0) return 0;
+
+  const sum = numsOnly.reduce((acc, n) => acc + n, 0);
+
+  return Math.floor(sum / numsOnly.length); 
+}
 
 module.exports = average;
+
+
diff --git a/challenges/unit-testing/writing-tests/largest-number/largest-number.js b/challenges/unit-testing/writing-tests/largest-number/largest-number.js
index 4036dd74..ba86c168 100644
--- a/challenges/unit-testing/writing-tests/largest-number/largest-number.js
+++ b/challenges/unit-testing/writing-tests/largest-number/largest-number.js
@@ -1,6 +1,6 @@
 function getLargestNumber(array) {
   let largestNumber = array[0];
-  for (let i = 0; i < array.length; i++) {
+  for (let i = 1; i < array.length; i++) {
     if (array[i] > largestNumber) {
       largestNumber = array[i];
     }
@@ -9,3 +9,4 @@ function getLargestNumber(array) {
 }
 
 module.exports = getLargestNumber;
+
diff --git a/challenges/unit-testing/writing-tests/largest-number/largest-number.test.js b/challenges/unit-testing/writing-tests/largest-number/largest-number.test.js
index ce674209..ffa01d88 100644
--- a/challenges/unit-testing/writing-tests/largest-number/largest-number.test.js
+++ b/challenges/unit-testing/writing-tests/largest-number/largest-number.test.js
@@ -1,13 +1,11 @@
-let getLargestNumber = require("./largest-number");
+const getLargestNumber = require("./largest-number");
 
-test("returns largest number in array", function () {
-  // Arrange
-  // Act
-  // Assert
-});
+test("returns largest number in array", () => {
+  const input = [3, 21, 88, 4, 36];
+  const copy = [...input]; // to check original array is unchanged
 
-// example
-// input: [3, 21, 88, 4, 36];
-// expected: 88;
+  const output = getLargestNumber(input);
 
-// also test that the original array hasn't changed
+  expect(output).toBe(88);       // largest number
+  expect(input).toEqual(copy);   // original array unchanged
+});
diff --git a/challenges/unit-testing/writing-tests/remove-vowels/remove-vowels-in-array.js b/challenges/unit-testing/writing-tests/remove-vowels/remove-vowels-in-array.js
index 6f4e06bf..307f8359 100644
--- a/challenges/unit-testing/writing-tests/remove-vowels/remove-vowels-in-array.js
+++ b/challenges/unit-testing/writing-tests/remove-vowels/remove-vowels-in-array.js
@@ -1,16 +1,8 @@
-let removeVowels = require("./remove-vowels");
+const removeVowels = require("./remove-vowels");
 
 function removeVowelsFromWords(words) {
-  let result = words.map(function (word) {
-    return removeVowels(word);
-  });
-
-  return result;
+  return words.map(word => removeVowels(word));
 }
 
 module.exports = removeVowelsFromWords;
 
-/*
-    input: ["Irina", "Etza", "Daniel"]
-    expected output: ["rn", "tz", "Dnl"]
-*/
diff --git a/challenges/unit-testing/writing-tests/remove-vowels/remove-vowels-in-array.test.js b/challenges/unit-testing/writing-tests/remove-vowels/remove-vowels-in-array.test.js
index ee739e22..2f5f48fc 100644
--- a/challenges/unit-testing/writing-tests/remove-vowels/remove-vowels-in-array.test.js
+++ b/challenges/unit-testing/writing-tests/remove-vowels/remove-vowels-in-array.test.js
@@ -1,11 +1,11 @@
-let removeVowelsFromWords = require("./remove-vowels-in-array");
+const removeVowelsFromWords = require("./remove-vowels-in-array");
 
-test("remove vowels from all words in array", function () {
-  // Arrange
-  // Act
-  // Assert
+test("remove vowels from all words in array", () => {
+  const input = ["Irina", "Etza", "Daniel"];
+  const expected = ["rn", "tz", "Dnl"];
+
+  const output = removeVowelsFromWords(input);
+
+  expect(output).toEqual(expected);
 });
 
-// example
-// input: ["Irina", "Etza", "Daniel"]
-// expected output: ["rn", "tz", "Dnl"]
diff --git a/challenges/unit-testing/writing-tests/remove-vowels/remove-vowels.js b/challenges/unit-testing/writing-tests/remove-vowels/remove-vowels.js
index e5bb67ba..514c1722 100644
--- a/challenges/unit-testing/writing-tests/remove-vowels/remove-vowels.js
+++ b/challenges/unit-testing/writing-tests/remove-vowels/remove-vowels.js
@@ -19,11 +19,3 @@ function removeVowels(word) {
 }
 
 module.exports = removeVowels;
-
-/*
-  Let's trace this piece of code - what is the value of result with this input
-
-  let result = removeVowels('samuel');
-
-  what is the value of result?
-*/