How can a 15 year old invest in the stock market?

[Seth]

I want to know how i could invest in the stock market as a 15 year old

[Robert D]

You can't.

You need to be able to pay a broker to do it on your behalf.

[Viril Litty]

With parental consent, or through a parent's account.

[Doctor Deth]

you can't without a parent's help

[A Nobody]

In the United States you must be 18 years of age to open a brokerage account in your name.
This is covered in Federal Law and Contract Law.

You can have one of your parents and./or guardian open a custodian account for you using your social security number. When you turn 18, the account can be closed and the assets moved to an account in your name.

[Max M]

You can invest at any age. There's no age limit. You just need a parent to sign off on the account if you're under 18.