I have a fear of singing in front of people: what should i do?

This is something that's hard to just get over. It takes lots of practice and support from others. The first step is learning to have confidence in your own voice - sing alone whenever you can - I bet you sound great!
Just remember that that's how good you can sound when you get up there - aim for pleasing yourself with your performance, not an audience.

I've found that it's harder to sing in front of a few people than a large number, but it might help to practice in front of your theatre teacher or a few friends - ask the choir director at your school or music director for your show if he/she is willing to take some time aside to work with you.
It's all about building confidence.

I still struggle with this problem. I can sing my heart out on stage in a musical (alone or in a chorus), but I'm shaky and not nearly as good as I can be in auditions, and other types of solo performances.
Good luck!

First, sing in front of a mirror with a hairbrush. Trust me, this really works! And once you get comfortable with that, ask your mom or dad if you could have a family fun night to do kareoke (or however you spell it!) and fun stuff like that. And once you're comfortable with singing in front of your parents, try your friends or church or social group. Hope it helps!

let's try this:

when you get on stage close your eyes (blindfold if you can't) and sing

You should sing with your eyes closed many celebrities do it but because its cool but so if you did it no one would really notice

Trust me girl, I am too! My mom has heard me sing but no one else really. I HATE to be harsh but I would just turn around or blindfold yourself and sing your little heart out but if you don't wanna do that, idk what to do! Maybe just sing for little groups of people at a time and increase the number of people gently. Good luck!! You'll get there someday I promise!