With driver training, sure. Do you believe that he has the sense to learn car control and apply that when he gets aggressive?
The real issue with a '95 M3 is maintenance - a '95 is pretty old and will almost certainly need substantial work. (Very few people seem to be properly maintaining them at this point.) Typically, cooling system, suspension, bushings, and a few other things.
How are you handling maintenance? Will this be your responsibility? His? Is a shop dealing with it? Refurbishing an older BMW can be very rewarding - it'll feel like new, but it can be pretty expensive. And frequently, it's not optional.
2006 GMC Sierra 2500HD 4WD Duramax LBZ/Allison 6-speed
2002 BMW M3 Alpinweiß/Black
1999 323i KP/GTS2 Alpinweiß
1990 325is Brilliantrot/Tan
1989 325is S50B30US Alpinweiß/Black
1989 M3 Alpinweiß/Black S50B32 (321hp, ITBs)