Should we teach k-12 student's sex ed

Hey girl's i have a question for you. Do you think sex ed for k-12. What i mean i is by that is starting for K-2 teachers will teach them about good touch bad touch,that saying "no" is okay basically a form of teaching consent but not in a sexual way biy pesonal way. 3rd to 5th would still be expand that and slightly get into sexuality (since at that age they aren't really thinking about that). 6th grade will be about sexuality and tolerance to people "different" and about reproductive systems. 8th grade can be taught about protection and so on so forth. Please explain why thank you