Cake in the Sky (1973)

This movie is an adaptation of a book by Rodari, a famous Italian poet and writer of children literature. A group of children in the outskirts of Rome bump into a spaceship that landed nearby. Soon the event draws the attention of the media, the military and rich entrepreneurs. The spaceship is pointed as the evil to fight against by the authorities, and nobody trusts the kids, who on the other hand try to preserve the spaceship (which is actually a harmless space-cake). –IMDb