Use this teacher tool to show missing parts (addends) of the whole numbers. Just cut halfway horizontally on the page to separate one card from the second. You can fold the right/left flap to show the first addend or the other to show the second addend.This set includes parts for numbers 5 thru 10. You may even wish to reduce the size of these cards so that your students can have their own sets for practice. Very useful as a visual aide to see those missing parts of whole numbers!