Nedda Gilbert, MSW, Educational Consultant, and Author
It sounds as if you're trying to "beef" up your application in anticipation of applying to a competitive college. If this is the case, taking these extra classes may help. If you have the option of taking fluffy electives like "The Art of Baking" or a math or foreign language class, the latter two classes are preferable. The more demanding and academic your coursework, the better. Of course, it would be ideal if you could get an A or high B in each of these "extra" classes. It's a good idea to take more rigorous courses. But you'll need to ace them too.
It's unclear if you have a particular strategy here. If you intend to major in engineering, or the sciences, an extra math class with an A in it may give you a boost. If you've performed poorly in math in school, or got a lower score than you hoped for on the SAT or ACT, that extra math class - again with an A or high B grade - can be redemptive.
As for an extra language class, most schools require three years of language. If you already have that, going for a fourth year, particularly if you hope to become fluent, might be very compelling.
Of note, if your current grades and scores are somewhat lackluster for your target college, an extra math or foreign language class will not win you admission. Instead, think of those extra classes as a little bit of weight pushing the scale in your favor.