What is the general guideline in regards to LORs? 2 from science and 1 from non-science teacher? What if I do not have a non-science teacher? is that going to eliminate a lot of schools?
Many will let you do substitutions: employer, volunteer coordinator, physician, other adult (non-peer) who knows you well. Some schools require you to petition or write an explanatory letter is you provide a substitute. Others give guidelines on-line or on the Secondary application for this situation.