Do community college classes in which are taken during high school(such as precalc, calc, and language), boost your GPA when you apply to colleges?
Community college classes do but they must be college and not college prep level. For instance pre Cal does not count as a gpa boost since it is offered at the high school level. I assume you mean gpa boost for freshman admissions as applying as a transfer means only community college courses count and those have no gpa boost
^^ that’s exactly what i’ve been told. The courses need to be taken in a college setting, not in the high school.
I think what the OP is referring to is the GPA boost you get from taking a-g classes either via dual enrollment or straight community college, while in HS. And yes, you do get the GPA boost when UC/CSU schools calculate your GPA when you take these classes. But for leveling purposes you only get the boost for up to 8 semesters worth of Honors, AP or DE/CC classes in 10th and 11th grade. Anything beyond 4 full classes/8 semesters is treated as a regular class from a UC/CSU GPA perspective.
Keep in mind that taking a college class while in high school and getting an A will look great on your application regardless of whether it affects your GPA. My son took Statistics at a college because his high school would not allow him to take it because students there are limited to one math class per year. I think this extra class gave a boost to his UC application and may have been regarded as similar to taking one more AP class.