What to do if you wanna come out as bi to your school but scared that your school won't except you?

This is a difficult question. I think you should be who you are and want to be I know it is hard to not be accepted but They should accept you for who you are

If you may be in danger of bullying or something, better stay in closet

The first question to ask yourself is why you want to come out. Not everyone needs to know all aspects of your life or who you are. So, if coming out is not necessary, then don't come out. Sometimes those you are young or immature simply don't have the life experience or the understanding to welcome you with open arms (as they should). So, if there is not a powerful reason to come out, you may want to save doing it later in life, with friends that are older and more mature, and consequently, more likely to accept you for who you are - whether bi or not. However, if you believe it is important that these kids at school know, then do so. You will need to understand that not everyone at that age is able to graciously accept the news. They may laugh or poke fun. However, in the end, it doesn't matter what they think or say because, as my mom always said, "what other people think of me is none of my business." Take care.