Use Oreo cookies (Double Stuff work best for this exercise) to model the phases of the moon.
Split the cookies open and scrape off the appropriate amount of cream filling, so you're left with the desired "picture" of the moon.
You could use a whole bunch of these and create the whole cycle. Use some frosting to "glue" the cookies to a plate in the appropriate order.
Or, you could use it as a quick, fun assessment - give each student one cookie and have them pick one of the moon phases out of a hat. They then need to use the cookie to illustrate the phase they selected.
Don’t you just love her idea about a formative assessment where they pick a phase out of a hat and then have to create it following the original experience! What a terrific follow-up ...Oh those simple ideas!
I was also thinking of a homework assignment where they connect the "concrete" (oreo model) to the "representative" model and have them draw the phases of the moon on a piece of paper using their own model as a "resource." Lastly, the "abstract" model would come on the test when they had to choose the correct illustration to show the moon phases using actual NASA photographs. Huuuummm...maybe I could get Karen from Science Matters to pull that together for one of her posts.