How do you tell your parents that you have your first boyfriend but you are only in the 7th grade?

Answering with lack of frivolousness, I think it is best for you to be honest about it with your parents. Sooner or later, they will find out, and who knows, you might not even be able to be friends with your boyfriend afterward. You should be the one to tell them. Seek your mom or dad or whichever one of them you think would be easier to talk to and just tell them straight out. Dont try to dance around and then hope that they will catch onto what you're saying, even if they will. Most likely they will tell you that you're not ready for a boyfriend, but just hear them out. Be sure they hear your view of things too.