Challenge the kid to come up with an alternative to money, a barter system, or an alternative way to store value
Let the kid come up with a proposal on whether their parent should max out 529 contributions or do something else with the money
Find a way for the kid to spend a week living at an alternative house. Punk, coop, intentional community. Spend time with people living in a cooperative environment not focused on money
Challenge the kid to find the "best" job they can get. Write 750 words each day about what they learn during the search process. What constitutes "best"?
Ask them to find and interview 10 people on the subject of money. Come up with questions. Edit the interviews.
Make a game that allows the kid to build different cash flow scenarios. As they learn about more concepts, they need to fold them into the gameplay. College, debt, savings
Mandate the every summer must be spent out of the country and the kid needs to pay for it. They need to get a job during the year to finance the trip. Or figure out how to get a summer job.
Challenge a kid to start a business. Give $500 in startup capital.