I saw a movie when I was little and I can't figure what it was. It was about a kid you found something and gave him powers. And Aliens try to get it. The aliens are people at first and then they can change in to this monster. And at the end they change his friend into a giant grasshopper or something please help me.

Guyver (1991)

Guyver (1991) (http://www.imdb.com/title/tt0101988/)

Mark Hamill (as Max Reed) is the one who gets turned into Grass Hopper.

Guyver (1991) - IMDb user comments (http://www.imdb.com/title/tt0101988/usercomments?start=20)

Hope this helped.