Practice Coding
hands-on challenges drawn from across the courses. Pick one, write the code in your browser, and check it against the worked solution — no account, no setup, nothing to install.
Practice coding with interactive exercises, challenges, and real projects across Python, JavaScript, Java, SQL and more.
Reading a lesson and writing the code yourself are different skills, and the gap between them is where most people stall. These challenges exist to close it: each one isolates a single idea you have already met — a loop, a dictionary lookup, a string method — and asks you to reach for it without the lesson in front of you. If a challenge feels impossible rather than merely hard, that usually means the underlying lesson is worth a second read; each one links back to where the topic is taught.
Start with the beginner set even if you have programmed before — they are quick, and they confirm the basics are solid before the harder ones assume them. Prefer working through a whole language in order? Browse the full course list instead.
Challenges by Course
Pro Tips
- • Start with Easy challenges to build confidence
- • Read the hint if you're stuck
- • Try solving without looking at hints first
- • Experiment and modify the code
- • Check the console for output
Hello Name
Easy
Create a program that prints a personalized greeting with your name.
Calculator
Easy
Write a program that adds two numbers and prints the result.
Temperature Converter
Medium
Convert Celsius to Fahrenheit using the formula: F = (C × 9/5) + 32
Even or Odd Checker
Easy
Check if a number is even or odd using the modulo operator (%).
List Manager
Medium
Create a list of fruits, add new items, and print each one using a loop.
Variable Practice
Easy
Declare variables using let and const, then log them to the console.
Array Methods
Medium
Use map() to double all numbers in an array, then filter() for evens only.
Function Creator
Easy
Create a function that greets a person by name.
Object Builder
Medium
Create an object representing a book with properties and a method.
Basic HTML Structure
Easy
Create a basic HTML page with header, main content, and footer.
CSS Styling
Medium
Style a card component with border, padding, shadow, and hover effect.
Flexbox Layout
Medium
Create a flexbox layout with three equal-width columns.
Hello World
Easy
Write a C++ program that prints 'Hello, World!' to the console.
Vector Operations
Medium
Create a vector, add elements, and iterate through it.
Class Creation
Medium
Create a simple Person class with properties and a method.
LINQ Practice
Hard
Use LINQ to filter and transform a list of numbers.
Variables & Types
Easy
Declare variables of different types and print them.
ArrayList Operations
Medium
Work with ArrayList - add, remove, and iterate through elements.
PHP Basics
Easy
Create variables and use string concatenation in PHP.
Array Functions
Medium
Use PHP array functions to manipulate an array of numbers.
Basic SELECT
Easy
Write a SELECT query to get all columns from a users table.
JOIN Tables
Hard
Join users and orders tables to see who ordered what.
NumPy Arrays
Medium
Create and manipulate NumPy arrays for data processing.
Data Preprocessing
Hard