Addition Facts Self Checking Flash Cards for Sums up to 20

Solve addition facts with sums from 11 to 20 and independently verify the answer using the card's self-checking fold.

Practice mental addition strategies, or use counters as a support, before checking each solved problem.

Assemble the cards following the fold instructions (fold right-third under, then left side over the picture so only the word/answer shows) before first use, and reinforce with lamination for a durable, reusable set.

Use a paper clip or clothespin to hold each card closed if students tend to peek before solving.

Set the cards up as a math center, small-group station, or morning tub activity, and provide counting objects for students who need more support than mental math alone.

Addition fact fluency — 177 cards give repeated practice across every sum from 11 to 20.

Self-assessment — the fold-open answer format lets students check their own work immediately without a teacher or separate key.

Flexible strategy use — students can solve mentally or with counters, supporting different levels of readiness on the same set of facts.

Independent practice routines — the format is designed for center, station, or small-group use without requiring direct teacher supervision.