Floating Ping Pong Ball at Steve Spangler Science. Link doesn't work, but you get the idea from the picture. I have tried this with the straw and ball only and it is difficult, but possible. The addition of the water bottle top seems like a much better way to do it especially with younger kids.

Floating Ping Pong Ball at Steve Spangler Science. Link doesn't work, but you get the idea from the picture. I have tried this with the straw and ball only and it is difficult, but possible. The addition of the water bottle top seems like a much better way to do it especially with younger kids.