Addition and Subtraction

Models for addition & subtraction problems. This website is great at explaining how to classify the different types of addition & subtraction problems the standards ask us to teach. A great framework for helping students conceptualize word problems!

Twenty Frames (PDF) (Luvaas/Albers).  Twenty Frames build upon students' experiences with Ten Frames in K-2.  They can be used to help model addition & subtraction facts, particularly with "Doubles / Doubles +1" & "Build Thru 10" strategies.  When doing 1 second flashes with Twenty Frames, follow-up with the four visualization questions:  "How many on top?" "How many on bottom?" "How many altogether?" "How many to make 20?

"Thinking Blocks" Models for addition & subtraction problems.  This interactive website is great at modeling how to solve the different types of addition & subtraction problems the standards ask us to teach.  A great framework for helping students conceptualize and practice word problems!