Two painted wooden bodies. The prism as well as the cuboid have the same volume, which is easy to calculate. All sink when weight down (eg. with coins) with interesting movements. Demonstrations in the aquarium, with an inlaid floor protection plate.
1x prism (LxWxH): 15 x 15 x 11.5 cm
1x cuboid (LxWxH): 15 x 15 x 6 cm
Use: 8th grade