Yesterday, we tried to make the balloon move along the piece of wool by taping it to a straw that was on the string. When we let the balloon go, the air came out, but it didn't move! Oh no!!
Today, we tried again. We changed two things...one was the length of the straw...we made it longer. We also changed the wool to nice slippery fishing wire. Watch what happened this time!!
Carolyn told us that it worked today because there was less friction. Just like if you fall over on slippery grass or wet concrete.