Float or sink, or both?

On Tuesday we continued exploring properties of solid objects by first guessing and then testing whether they could float, sink or could do both. We discussed what could affect the difference, air, shape, angle etc. We also looked at how fast or slow some things sank. 

When you press somethings down they sink, if they were floating before. Saga: "Rocks sink in water". Leon: " but rocks can also jump on water!". Yes! We concluded that it depends what shape the rocks have, how they touch the surface, in what angle, and at what speed. 

Maya: A plastic bucket can float in water, but if you put a stone in it it will sink! Air helps some things float, the ball floats because it is hollow."