Hi people, I am going to be a sophomore this year, and I am taking: Chemistry Honors, and World history (regular) . I have taken Biology (regular) last year. (There are no honor/AP classes for bio and world history)
I am thinking of taking the Chemistry, World History, Math 1, and Biology subject tests.
Which of those should I take, and how many subject tests is ideal for good colleges?
Do I need the AP equivalent of any of these tests (more specifically the biology test) , or can I take them with the regular version of the class?
2 tests are the usual. Take chem and wait on math till junior year
ok
Only a handful of colleges even require SAT IIs. Perhaps you should wait until those crystallize in a year or two.
The SAT subject tests are supposed to cover the material in normal high school courses. Of course, if your high school courses are of poor quality, the SAT subject tests may expose that with low scores. Note that math level 1 covers algebra 1 and 2 and geometry, while math level 2 covers those and trigonometry / precalculus.
It is true that most colleges do not require SAT subject tests.
It’s not necessary to take an AP test for a subject test. I took the SAT Biology E exam while taking honors bio during my sophomore year. I think it’s doable to take SAT bio while taking regular bio. You’ll need to study a lot of things on your own though; for example, at school, I didn’t have to memorize the whole taxonomy/ classification part, but for the SAT test, you have to. Good luck 
Don’t take Math I, it is not considered very rigorous by colleges that require subject tests. Math II is a better choice.
If you take World History, you need to check when it is offered. It isn’t offered on every SAT date. But one of my kids took it and did well. If you like WH, high scores on a math/science and on a social science/English type test can make you look very smart.