I can speak for AP Physics and AP Chem.
Don't worry too much about AP Chem being 2 periods long -- Mr. Walz (the only AP Chem teacher) is great and he definitely makes the 2 hours bearable with his quality teaching and stories about his children.
If you're into labs, we do PLENTY of those (around twice a week).
Regarding AP Physics, there are 3 courses: 1, 2, and C. If you haven't taken calculus yet, start with 1 or 2. If you have, C is the way to go. Labs are definitely a smaller component of Physics compared to Chem. You're right, many people say that AP Physics at EV is a rough course. This is probably because Physics demands a more conceptual understanding of what you're learning. In Chem, you can sometimes get away with blindly following rules or using formulas. Not so much in Physics. But PLEASE don't shy away from taking it because of what you've heard; you will do well if you listen carefully in class and ask questions regularly.
For either AP Chem or AP Physics 1/2/C, it's pretty necessary to be strong at math (less so for AP Bio, as Arianna mentioned).
It's pretty cool you're interested in all three! In addition to what I mentioned above, make sure to consider what you're planning to major in. If you're looking to become an engineer, Physics is probably a better choice. If you want to go to medical school, perhaps Chem or Bio.
I'd also encourage you to go talk to the teachers and glance over the textbooks. They'll be able to provide more in depth info.
Physics - Mr. Lubbs, Mr. Miller, Mr. Higgins
Chem - Mr. Walz
Hope this helps!
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