stockings dont need to be full of crap and they are a fun Christmas tradition so ignore the bah humbug. generally ds's is full of things ds needs/uses/wants, past stockings have had:
Vouchers - xbox, iTunes, scratch card, driving experience, cinema vouchers for over Xmas hols with popcorn/sweet pack.
Clothes - adidas socks, touch screen gloves, footie team scarf
Football stuff: every year he gets a football (it's a big Stocking), maybe shin guards/stays, goalie gloves, etc. things he would get during the year anyway
Accessories : new wallet if he needs one, earphones, money tray for bedroom as he always had loads of change lying about, phone power bank, phone case
Smellies: deodorant, Aftershave
Games:if they are into puzzles, books, mini games etc they can be good if not don't waste money on them
This year he is into the gym and doing stuff at home so will get a small resistance band set for his gym homework, gym socks.
Last year we got ds a jar of black face pack cream to help with his spots which he actually loved and still uses every week or so on his tone.
A mini rubber/foam ball, usually rugby for shape, he always had one of these in his room he tosses about and last year's is a bit burst.
Treats : nice chocolate, pud in a mug, favourite sweets. Always a lindt santa.
All stuff he will love, use and most be would have needed anyway. Watch them over the next few weeks to see things they could use/need.