Phases of the Moon interactive display. MO Science Students put their heads in the middle and rotate. Great way to see that the only things that are really changing are the location and angle/perspective.

This has a moon phases foldable and worksheets. It contains quite a few manipulatives dealing with the moon phases. Great for remembering the moon phases in a middle grade classroom.

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.