It might not actually be a good idea to regularly apply a complex chemical mixture - which includes known endocrine disruptors - to the skin of a young, rapidly developing male.
Stuff I've recently tried-
Lucky Tiger! No burn, soothing and mild, fleeting scent. Maybe the best razor burn splash I've ever used.
Florida Water, it'll burn a bit and leave him with a smelling like a candy fireball.
Dominica Bay Rum with lime, He just must learn about Bay Rums!
Clubman, cus it's been around forever, smelling it just brings the 60's and 70's to my mind.
Adidas Dynamic Pulse
Has a light youthful,athletic modern scent.Contains great skin care ingredients like allantoin,Vitamin E.
Gillette Cool Wave Splash
+1 on the Nivea Energy Splash.Or a Nivea Balm.
I would perhaps suggest making a father & son shopping trip to find the answer. Maybe your boy will surprise you in his choice. I have a boy that's going to be nearing shaving age soon as well and I figure I'll let him make his own selection. Plus if he chooses something I like as well I can steal some of his!!
For a 12 year old, I would avoid splashes or anything with alcohol, and anything that we like or think is nostalgic . . . he's 12.
From a brick and mortar you really cant beat Nivea products. Go with the Replenishing Balm if he wants a more masculine cologne scent or the Sensitive Balm if he wants something more mild. Both are full of good stuff for your skin and his friends wont rag on him for smelling like "an old man" AKA us.
Also, as said above, if he likes the smell or does want to try a splash, then pick up the Nivea Energy Splash. It does burn a little, but certainly not bad, and not near what some of us use.
I'd stick with non-alcohol based balms. Let him try different scents and see what he likes. Nivea might be a good place to start, but I'd start off right with Trumper's or AOS personally