One conversation started a couple of birthdays ago when I bought him a swiss army knife - apparently there's something about teenagers and knives that a retired woodwork teacher wouldn't understand - I thought a book and possibly some Danish oil would be less controversial.
If he’s already whittling it’s a bit late for that conversation...
Get him a Morakniv 120. I really rate mine, esp for the price.
https://www.nordicoutdoor.co.uk/by-brand/mora-of-sweden/carving-whittling.html