• Down the rabbit hole

Down The Rabbit Hole

Alice's Adventures in Wonderland's author Lewis Carroll was a mathematician and a logician, studying and teaching geometry, linear and matrix algebra, mathematical logic and recreational mathematics at Oxford University. Follow the white rabbit and hurry to our whole new island, filled with missions based on Lewis' tricky Puzzles from Wonderland!

Dumpty Form

Nicola wants to build his own "Humpty Dumpty" and he needs your help figuring out how much material is required!

The Stick

Our robots need to saw a stick in several pieces, in a very particular way. Can you help them out?

The Hidden

Nicola wants to invent a method to search for certain words in poems. Help him create such a nifty algorithm!


After reading "Alice's Adventures in Wonderland", our robots decided to create their own Multiplication table.


Doublets (or: Word ladder) is a word game. Let’s change the rules - because, you know, we're rebels!

The Rows
Of Cakes

Loads of cakes cover the floor and our robots can't help but try and figure out a pattern behind the cakes' disposition. Give them a hand!

The Alice Island brings another novelty to CheckiO.
Before you publish your solution, you can choose in what category you’d want to publish it. Are we talking about "Puzzle" solution here and is your solution short and tricky? Or is it "Speedy"? Python might not be the fastest language out there, but there’s always a fast(er) way of doing things, right? Is your solution "Clear" - educational maybe, and thus accompanied by well written, good documentation? You can always leave your publication uncategorized if you don't know how to rate your treasure.

Welcome to CheckiO - games for coders where you can improve your codings skills.

The main idea behind these games is to give you the opportunity to learn by exchanging experience with the rest of the community. Every day we are trying to find interesting solutions for you to help you become a better coder.

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