P7 finished by scraping chalk into a tray of water and placing paper on top of the chalk in the water to make funky prints.
Some children wanted to be creative and swirl the chalk to change the pattern but soon realised that if they touched the water and broke the surface tension all the chalk sunk to the bottom.
We discussed that the surface tension in water allows some objects to float on the surface of the water even though they are denser than water.
The children had so much fun!!
