I am an incoming senior and am deciding which teachers I should ask to write my recommendation letters. I am not entirely sure what my major will be yet, but there is a possibility that I might go for STEM (environmental or food science would be STEM but other majors include economics and env. studies). My strongest recommendations, I believe, would come from my English and my Foreign Language teacher. The former can testify to my strong writing ability, work ethic, and critical thinking skills. The latter also thinks highly of me as I am the vice president of our language honors society and believes that I am highly distinguished from my peers - even the president. My science teacher would likely have a good recommendation as well but I am not so sure it would have the same impact as the other two. So I suppose the question is: would it be better to have two outstanding recommendations from humanities teachers or should I have one from a STEM teacher?
Check with the colleges of interest to see if they have specific requirements for LoR writers.
Check with your guidance counselor. In my school you would be advised to get at least one from a STEM teacher.
I would advise you to get a letter from a STEM teacher. What do you do as the president of the foreign language club? Is it something you might cover in an essay? Years ago one of the short common application essays was about your favorite EC.
Read the admissions requirements on the web pages of colleges you would like to apply to, because as ucbalumnus said, they may have specific requirements. Some universities have different requirements depending on the college/department/major. As a general rule of thumb, the more selective the university or the program, the more you need to pay attention to this.
At my child’s HS, they strongly advise all students to get one letter from a STEM teacher and one from humanities. Made complete sense to me, given that (a) colleges are looking for well-rounded community members and (b) young people inevitably change and develop new academic interests during their college years. My child is wholly committed to STEM and didn’t consider not arranging for a humanities letter.