Decomposing Numbers: can do an activity with the number cubes. Students roll a number. Put that number of blocks in the big circle then decompose into 2 smaller numbers. Give students a recording sheet.
Using Number Bracelets to Develop Number Sense. Like dot cards and rekenreks, number bracelets provide concrete practice for number combinations and composing/decomposing numbers. Check out this post for instructions for making and using number bracelets.