Forget investing. Nothing will pay off as much as you want in that incredibly short space of time. Apart from that, anyone who invests knows there's a very real risk of not receiving any return. That's why people diversify, so they can take a loss.
The advice to work is actually the best way to make money. Look for one off jobs. Handing out flyers for 8hrs a day. Dropping flyers into letterboxes. Will you earn $3000? No. But you'll reduce that debt to a more acceptable size. And you'll definitely learn that spending money requires earning money.
Also, EBAY! Sell your stuff! It sounds like you can't afford $3000 worth of stuff. Sell dvds, computer games, whatever you don't want. Plan to buy it back one day in the future when you have a job and have actually saved up for the stuff you want.
Like I said, you don't necessarily need to make 3k - although that's your goal - but if you do have to tell your parents, imagine how much better it will sound to say you owe $500 or $800 than $3'000.
Here is your best option: tell your parents. Legally, your parents cannot "kick you out of the house" at the age of 15. The worst they can do is take away your cell phone privilege, your TV or video game or internet privileges, etc... You need to tell them so that they can remedy the situation. They are probably going to make you pay everything back eventually, they might have you do a lot of chores, and you are going to have to do a lot of work to earn their trust back. However, trying to remedy the situation yourself is just about going to be a guaranteed failure. You are dealing with the big guys. You and your parents might end up with a much worse situation if you do not tell them and ask for help.
You should not have been able to sign any type of legal contract. I assume you signed up for something and lied about your age. You could probably get off not paying, but it would be considered unethical not to mention illegal to lie on a loan application.
If you want to pay them back, call and work out a payment plan with them. Tell them what you can afford to pay per month & get some type of job to earn extra cash. Or as someone mentioned, sell something. That is probably the quickest way to get some money.
And don't lie about your qualifications or go into debt in the future. Remember the borrower is servant to the lender.
EDIT: I see you used your parent's ssn. That likely means you also must have used their name & age, as a fraud alert would have shown up on the credit report if the name didn't match the issued ssn. If you can't pay it back, you need to tell your parents 'now' before the payment is late. Going delinquent will negatively impact their credit score, which will make it harder for them to take out loans in the future either for themselves or as a co-signer for you.
Your parents will need to call Paypal and explain. They might be able to file a claim of identity theft to get out of paying. Since you are underage, I don't think Paypal would be able to go after you either.
But if you were over 18, your parents & Paypal could technically press charges against you for identity theft & fraud. We all make mistakes, just make sure you learn from them.
Go to http://ftr.io/r/P9ENTX91 and sign up for free. It will credit $1.25 to your account instantly(you need a phone because it texts you). It will then pay you 25 cents each time it texts you which is about 4 times a month. http://www.CheddarBread.com are websites that offer various ways to get money added to your PayPal account(Listening to music, filling out surveys, playing games, watching videos etc).
Return all the items you paid for on credit. Only way you could owe Paypal is by using details that are not yours. Own up is all you can do. If you have items physically purchased online return them.... for a refund..
You can just not pay. Contracts are legally unenforceable on anyone under 18.
get a job
