Yesterday we pulled out our new math balance for the first time and explored the concepts of balance, equality and weights. The little centimeter cubes Honeybee is reaching for in this picture weigh 1 gram each, and we used them in conjunction with plastic hexagram weights to figure out the mass of a variety of objects: nails, a spoon, and grapefruits.
At one point, Honeybee and Jumping Spider got into a race to see who could fill their pan with weights faster—Honeybee won when she decided to dump the entire container of cubes into her pan. After this picture was taken, the race got wilder—as both sides started stealing weights from each other and adding other items (like nails) to their pans to try to make their pan heaviest. Things were getting out of hand and I had to call a halt and have them clean everything up before continuing our investigations.