I send school work through email but get a spam message saying it was block by spam filter. How do I fix this?

Every time I send a message that has to do with school work, I get a spam message saying it was block. I don't know what the problem might be bcuz I do make sure the address is correct, but its still sends me that message.

I send school work through email but get a spam message saying it was block by spam filter. How do I fix this?
What type of e-mail is the school using? Maybe you should try to open an e-mail account of the same type as your school. I never heard of a yahoo mail failing to pass a spam check. If I were you, I would call the school and ask for assistance.