If you (or your parents) like to cook, you could get some choice steaks (or other high-end ingredients) and make a nice meal that the whole family can enjoy.

Could also get a nice game controller if you’re into video games. Most first-party controllers seem to cost about $70 these days.

I dunno what the “smart” thing to do with $75 would be; $75 isn’t a whole lot of money in the grand scheme of things so investing it wouldn’t exactly pay dividends any time soon. Maybe buy 1GB of DDR5 RAM and in a year it might be worth $75,000 if the market continues its current trend.