These cards are a great resource to use with students learning how to fluently add and subtract within 20 and for students who need to practice finding the missing addend.
We use them like a game of "headbands" as a math center. Students find a partner and hold up the card to their forehead and the partner has to tell them the missing addend that will make 20. Both students get great practice finding the missing addend and they love that it turns into a game!
The two pages included in this freebie make one set. Print off as many sets as number of groups you plan on having.
2.OA.2 Fluently add and subtract within 20 using mental strategies.2 By end of Grade 2, know from memory all sums of two one-digit numbers.