I hope my rusty english is good enough to make this review understable for everybody. I am spanish, and i don't practice much nowadays.
I remember to have watched this film with my parents at home when i was a little boy. It impressed me and i was shocked by how society treat the boy, as a circus freak because the fear and misunderstanding about the disacknowledged things, however the little boy is not a bit of feared or ashamed or so, in the entire movie.
The final escene is so emotive. I also remember to be already guessing it right before the events where about to happen, so it wasn't a big surprise at all. But shocking, anyways.
I think it was a shocking and not average film for that year (1978). The spanish films wheren't like this one, definitively.
Recently i've found this film and i will definitively offer my 7 years old daughter to watch it. Same as i did when i was her age, we will watch it at home with my wife.
If you have the chance to view it, do it. I think childs would enjoy it.
At least, i did.