Poor bear was really upset as we cleared father's room in the care home. However he then went to his tutor.
As I have mentioned, bear goes to visit a maths tutor on the strict understanding that he doesn't go beyond his year, beyond what his school has taught him and that it is for fun.
Today the tutor allowed bear to play with non-Newtonian fluids. If you slowly push your hand into a cornflour and water mix then it is liquid, if you hit it, then the mix is solid. Bear and DH explained but I didn't keep up. I found a link on Wikipedia here, but I didn't understand it. The tutor (who is really lovely) then put some dry ice into test tubes, put a cork in and then they went outside to see the test tubes explode. Bear was in heaven.
DH was very impressed as well. When asked to give an example of a solid, bear said, 'sodium'. It just goes to show that YouTube is for more than just cat videos. For those, like me, that stick to cat videos, here is a favourite one of mine. I miss evil cat.