Is it a good idea to tell a friend that I have a crush on her even though I know she doesn't feel the same way?
That's tough. Do you think it will go well?
I don't know. I'm still the new kid on the block so I hope it works out fine for me.
Although you will be putting her in an uncomfortable position since you know she isn't going to return the feelings, it's probably best to be upfront and honest with her. Just know that there's a chance she will want to end the friendship. Sometimes people are uncomfortable being friends with people who have feelings for them.
I don't care. I'm ready to spill my guts out.
If you feel the need to tell her, then I think it's a good thing to do. She will appreciate the honesty even if she doesn't feel the same way about you.