The movie was about a young boy that knew the world was being taken over by aliens, his parents were turned into alien monsters and his teacher helped him defeat the threat. The aliens were aking a community under the ground, while the army were trying to surround them.

Invaders from Mars (1953) (http://www.imdb.com/title/tt0045917/). Actually, it was a doctor who helped him defeat the threat.

I agree with Purikivel and netknight; the 50s version was better. I was six years old when it came out and my grandmother took me to see it; scared the pants off me!