Village of the Giants

A young kid named Genius accidentally invents a substance that causes all animal life to grow. Genius' sister Nancy and her boyfriend Mike see the money making potential in the substance dubbed goo and plan to sell it to help solve the world's food problem. Unfortunately, a greedy young opportunist named Fred and the group of delinquents he hangs around with decide to steal the goo and use it for their own purposes... (imdb)