Are the expectations in Kindergarten too high?

This really is an opinion, not a question. My son is in Kindergarten and he is really smart. He keeps up with the work, however I think the expectations are ridiculous! They are doing pre-algebra and taking Spanish. They have to sit, focus and listen all day. It's full day Kind. cl. They have recess and gym of course and go for walks, but to sit all day at that age is ridiculous. I have periodically gotten a call from his teacher saying he can't sit down at all and is out of control. He is not mean, never bullies, never hurts anyone, etc. He just jumps around and likes to be silly. Some days he just dosen't want to learn. He has waves of it. He is fine for a few weeks and then falls off. Took him to a neurologist who looked at me like I was crazy for bringing him in. I just think the expectation of the work load and sitting for so long is too high for alot of children. I am sure many fall right into place, but not all kids are the same....What are your thoughts? Just wondering with the "community" thinks