10-20 Challenge

10-20 Challenge is a Grade 5 decimal game for adding and subtracting decimals. Students select six cards, arrange them into two decimal numbers, choose addition or subtraction, and calculate the result. Because they control how the digits are arranged, the game gives them practice with decimal place value at the same time they are working on computation.

Use it for small-group review when you want students making choices about numbers instead of receiving every problem fully formed. The target-based scoring also gives them a reason to estimate where an answer may land before calculating exactly. Sign up free to generate teacher-ready lesson support for 10-20 Challenge. No credit card is required, and the account includes 3 lesson generations for life.