If DS annoys you over the summer holiday you can get your own back by telling him the reason he needs his name on his rugby shirt is so that when he gets knocked out they know what his name is
Its a complete pain but so much kit goes missing in the changing room is worth the effort to name everything worth more than a couple of pounds!
If you have the energy its worth checking kit/blazer/shirt/trousers when they get home on a Friday so if something is missing/not theirs they can be dispatched to look for it before too much time elapses.
Over the years we have ended up with several un-named, greying shirts and t=shirts
Hope your DS has a great time on Thursday.