I'm still loving what Ania said,

"when you accelerate your kids they are not going to be in a class of smarter students, they will only be in a class of older students."

So well put!

I think I worried about the Calculus trap too long and was patient with teachers/admin who kept wanting to put off algebra for that reason. I guess I'm coming to the realization that my DS13 is in high school because he needs to grow up before going to college--not because he's not able to do it. He's interested in graduating a year early and maybe do a foreign exchange program or language institute with "time saved".

My answer to the question about if you still get As are you challenged? Sure. I'm not an educator, but I would think the process should be that you introduce a new topic, do some problems, review what went wrong if there are errors, then test. That intermediate step of review should mean that a kid can make mistakes, learn, and then still get As...don't you think?