Step 1: Things you would need
This is the best toy with the least time needed to make and from only 2 things.
1. An Old sampoo or conditioner bottle. (sunsilk or pantene) I got mine from my moms closet.
2. A balloon or 2.
3. 5 second of time.
Thats all you need to build this amazing toy.
Step 2: Method
So how do you play with it you must say right ? .......
Step 3: Fun fun and more fun.
Just squeeze the bottle and the balloon should inflate to the maximum it can....
leave it quickly and then squeeze on the sides. This will make the balloon suck all the way inside the bottle and then when you squeeze on the front it will blow up again...it would continue to do like that. I actually made two to have more fun. Also if possible have a rubber band on the neck to prevent air from leaking.
Now you have your amazing toy. Go make it and experience the great fun.