Hide your keys from your son. Do not create a situation where he could give those keys to friends via peer pressure. Kids at a young age are very easily convinced by older peers that they are doing nothing wrong.

Educate your son on this, and maybe consider splitting your wallet among multiple keys. I personally have 2 Trezor devices and one Ledger. Looking at a 4th. Each member of my family has a copy of specific keys (or partial sets of keys where they need to unite to unlock the cryptocurrency). This is so no single hiccup can clean me out.

Good luck, and I'm glad your son is learning!