The movie starts with a boys mother picking him up from a hospital or mental institution, they leave the hopital in a car, maybe convertible and the boy does not speak, but he keeps holding up these pieces of paper with small holes cut in it and looking at the passing scene as they drive through the holes in the paper. It seems to me the boy does not speak and perhaps the father ends up leaving at some time in the movie because he can not handle the sons mental problems. The movie was probably made in the late 60's...

This sounds very familiar to me. I don't have an answer now, but I want to find my way back to this. I hope that's acceptable.

I have a very strong mental image of the boy with the pieces of paper.

I'm going to check out a couple of titles that came to mind. I saw them so many decades ago, that I need to read summaries if I can find them.