Small scale version of this with the kids 9 & 12

They receive a % of chore/pocket money into a lightning wallet.

The eldest splits the payment into additional wallets for saving / spending / specific event-or purchase wallets.

When goals are reached we procure the items with them if vendors are not btc enabled, they transfer funds to our lightning wallets.

If out and about and they find something to purchase, same deal we assist the fiat payment as needed and they pay realtime in lightning.

Simpler than a bank account, they can see funds in & out and how savings are working.

Start early, encourage budgeting, make it simple.