"These are way more fun than flash cards!"
That's what my second graders said after sorting out all of the doubles and their partners! Each doubles fact is arranged on two separate puzzles, one with images for the doubles and numerals for the total, the other has images (which match the other puzzle) for the total and numerals for the doubles.
Each group of 4 puzzles has a matching set of worksheets (I like to refer to them as exit tickets, or tickets out the door). These are a great way to check your students' work with the puzzles. One set is missing sums, the next is missing the second addend, the third is missing the first addend, and the last is a mixed set.