All I can recall is 2 large giants... possibly of 2 different colors... they may have been animated...

In the end one is looking for the other and keeps yelling his name... example..."Blue Giant!"

I know it sounds like "War of The Gargantuans", with the colored giants and all... but, I don't think they would being showing that film to 6 year olds in 1980... in school...

No clue...