Here are 42 pages of subtraction flashcards to the difference of 20. Perfect for meeting the mental math Common Core standards in Kindergarten, 1st, & 2nd.
Each page has 6 flashcards. There is a page without answers, then the following page includes the answer. I found the answer side is helpful when students are using them as part of a center, that way they can double check their answer or a fellow students answer.
I personally have cut out each flashcard then used double-sided tape to put the non-answer card & the answer card back-to-back, before laminating. I know it's a little extra work, but I for me it was worth it so the students have the answers readily available without having to dig around for them.
These flashcards are perfect to use with my Fact Swat game. Check it out in my store.