Fun! I'm going to do this for fluency next time I do math workshop in my class! You need as many Post-its as problems you will give, a Sharpie marker, and a pencil. Write the the first problem on the front of a Post-it note at the start (maybe this one is a different color). Now write the answer on another Post-it with a new problem on the underneath (in pencil). Students have to work problems and then search for the answers. Great way to get students doing math and get them up and moving!
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BEST SELLER! Grade 3 Common Core Task Cards for EVERY Math Standard. This document makes a fantastic math center and provides an open-ended math problem for each standard. This is great as a math center or math problem of the day.