S.P.
I agree, spend more time in the classroom. She can't say "no" to you, at least on a consistant basis. You have a right to visit your daughter's class.
As for the extra credit--It's actually quite common with combined (or not) classes, the GT kids receive extra credit or enrichment activities for credit. Both of my older boys have been in GT classes since first grade, and have had their share of extra credit, when the other kids did not.
I've had the experience of not liking my child's teacher. Whatever you do, please don't let your feelings influence your daughter's about her teacher or classroom environment. Focus on the positive!
Another thing I've realized, alot of GT teachers were once GT students! And on average, GT kids are just different LOL. I've met some teachers that were on the strange side to me---both in attitude & social aspect, and classroom activities & assignments. But in the end, my child LEARNED alot from each of them.
Good luck!