Brain games for curious kids
Logic puzzles that make math feel like a game. Start with an Easy 4x4: fill the grid with 1 to 4, no repeats in any row or column, and make every cage hit its target.
How to play
Fill 1 to 4
Every row and every column uses each number once.
Hit the target
Each outlined cage must make its number with its operation (+ - x ÷).
Check the answer
Every Brain Focus book has a full answer key in the back.
Questions
How do you play a 4x4 Calcudoku?
Fill the grid with the numbers 1 to 4 so each row and each column uses every number once. Each outlined cage must make its target number with its operation (+, -, x or ÷).
Is there an answer key?
Yes. Every Brain Focus book has a full answer key in the back.
Where do I get the puzzle books?
The Easy 4x4 Calcudoku books are from Brain Focus Books at brainfocusbooks.com.
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