What happens when you put Jello inside of straws? JELLO WORMS! You rubber band the straws together. Pour the jello mixture in the straws. The liquid will fill the straws and around the outer straw. Place it in the fridge until it gelled. Pull out the clump of banded straws. Run warm water over the straws for about 5 seconds, and the fabulously disgusting life like worms slide out! So gross but boys will LOVE it!