No, because not all "ideas" are equal. A perfect example has already been posted above.
However I do think people should be exposed to as many different beliefs, opinions, thoughts, and "ideas" as possible. Even those we find objectionable.
I think kids would get a kick out of learning alchemy
Definitely not. There is only so much that can be covered by an educational system so we need to be economical with what we ask our children to learn. There's not enough time to give equal attention to every idea under the sun.
Some ideas are so stupid that they don't appeal to anyone
I believe in educating people, even if it meant having to deal with alchemy. It does prove that certain beliefs are worth knowing about, but otherwise useless. Picking locks is useful, even when deemed immoral to teach. Forgot my keys inside my new flat and since the lock is extremely safe, I had to borrow a random teenager to climb in my window. Now, if I knew how to make thermal projectiles out of nothing, I could just blow myself in to pick the keys up - but then I wouldn't have a door to worry about, so basically I'm logically impaired. That, on its own, is a lesson worth teaching to the kids.
Because not all ideas are equal in value.
Some are false and/ or ineffective
There are certain ideologies that should be in schools and some that should not. A lot of it has to do with objectivity versus subjectivity. however, no viewpoint should be censored regardless of how others interpret it. In education - especially colleges - we have a lot of situations where an echo chamber emerges around students that begin refuse to listen to other perspectives, causing individuals to garner a wider divide between their ideaology and those that are outside of their personal bubble.