If you do the "four things"..

[drspouse]

What have you done for "something you need"?
Previously I've done hobbies, things for bedrooms, and nice plates/cups but they don't need any of those this year!

@mrsm43s

I dunno, I provide my children with things they need, things they wear and things they read anyway as part of my responsibilities as a parent. I'd only consider the "want" to be a present and something over and above what I'd be buying them anyway.

But some families actually can't afford this year round and can't afford loads of presents. If a DC doesn't get these things all the time then they love getting them at Christmas - or my 2 do anyway.

I always give my DC winter clothes for Christmas, at least one book and other things they need like stationery, toiletries. They have Minnie Mouse hairbrushes this year and DS has a glasses case.

Skincare products or gift cards to clothing/accessories/hobby related stores might work. Could also be subscriptions to stuff they might need for study (like professional slideshow makers if they use that for school projects or photo editing programs that are beginner friendly, etc) or tech stuff like ring lights or portable chargers or headphones.
I'm not really following the whole 4 things scheme, usually 2 things coincide in one gift.

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For 18 year old boy:
want - record player (that plays vinyl records!)
need - two dozen pair of identical socks and one dozen of underwear
wear - hoodie
read - anime books from his favorite Japanese series

For 15 year old girl:
want - refrigerator for her bedroom
need - appointment with hairdresser for professional cut and dye job
wear - leather boots
read - book of piano sheet music