Legal/Postal Advice? Urgent!!!?

I am 15 years old, and am a freshmen in high school. About a week ago somthing happened where I said somthing or someone else said somthing to trigger a girl to ask me if I destroyed her neighbors mailboxes. I responded with "Yea, DID do it" completely sarcastically, and then she went off how she was going to the police. I made it clear in class I had no involvement with it. However, my recent juvenial record is not good. They called my house and all though they have no physical evidence associating me to the crime, they say I was bragging about it in school. They want me to meet with the familys tommorow and the police department after school. However, if I was being arrested don't I have civil rights and do not have to meet with anyone, the right to remain silent ect. I think I should sew for slander! But besides the point, what action should I take, my dads on thier side and thinks I did it too. My question is how I can outsmart my town and use the rules/laws against them?

Your best bet. Don't say anything. Deny, Deny, Deny, and then remain silent. Refuse to talk to anyone without a lawyer present (and they will call a public defender down to meet with you if you can't afford one, which... in my opinion wouldn't be smart to pay money for since they have nothing on you.)
Its really your word against some girls. Regardless of your record, they have no physical evidence. Good luck.

You placed yourself in a real pickle by publicly admitting to committing the offense. The police are giving you a chance to come in and talk about it, which is better than being arrested, and indicates that all they have is your public statement. Decline to meet with the families, then meet with the police and tell them what you wrote here -- that you said it sarcastically. Without physical evidence or a witness, they don't have much of a case.

uh...hey? Perry Mason wannabe?

Sit down, tell the truth, and lose the attitude.