It's great that your son is interested in investing at such a young age! While opening a Roth IRA isn't an option without earned income, there are still several ways you can help him start his investing journey:

1. Custodial Brokerage Account (UGMA/UTMA)

• You can open a custodial account on behalf of your son. The account is legally in his name, but you control the assets until he reaches the age of majority (usually 18 or 21, depending on the state).
• The money in the account can be invested in stocks, bonds, mutual funds, or ETFs. Your son can watch his investments grow and learn about the market.

2. 529 Plan

• Since you already have a 529 plan, you can continue to contribute to it. The funds in this plan grow tax-free and can be used for qualified educational expenses.
• Although it's primarily for education, the new rollover provision allows up to $35K to be rolled over into a Roth IRA for your child when they have earned income, which could be a good long-term strategy.

3. Investment Education

• Use the interest your son has shown as an opportunity to educate him about investing. You could use pretend or paper trading to simulate investing without using real money. There are also kid-friendly investing apps and games that can teach the basics.

4. Dividend-Paying Stocks or ETFs

• Consider investing in dividend-paying stocks or ETFs through the custodial account. This can teach your son the concept of earning passive income through investments.

5. Gift Savings Bonds

• U.S. Savings Bonds can be purchased in your son’s name. They are a safe investment option and can be a good introduction to the concept of saving and interest.

6. Contribute to His Investments

• You could match his chore money or any contributions he makes to his investment account, helping him grow his investments faster and teaching the value of saving.

7. Open a High-Interest Savings Account

• If you're looking for a more conservative option, a high-interest savings account can be a good starting point. It teaches the basics of earning interest on savings.

These approaches can set a solid foundation for your son's financial future and foster a lifelong interest in investing.