Let's face it, any pre-teen does not need skincare. Any pre-teen should only be using a gentle cleanser, perhaps a little moisturiser if the skin is dry and of course, a good sunscreen. That's it. End of.
The trouble is, social media has resulted in many pre teens going hell-for-leather on unnecessary and over the top skin care products; many at the cheaper end of the market being, basically, glycerine in very expensive packaging. The more specialised products are designed for specific skin conditions and in the main (that is, unless you know what the need is) should only be used after consultation with a skin care professional. After all, some can be very expensive.
By skin care professional I do not mean TikTok and the rather challenging so-called influencers who are in many cases doing more harm than good, both to their own skin as well as persuading other "Sephora Tweens" to use products which may result in more long term damage than good.
Many of the brands themselves are causing these issues by using colourful packaging and push-down pumps. This is further complicated by many of these brands having tween "brand ambassadors". I am not going to name names but parents should be aware of any bright packaging and "cool" names; the reality is that some of these may actually be damaging to children's skin.
Parents may wish to read the ingredient trees and be especially aware of any products containing active ingredients such as Vitamin C, Glycolic Acid (or any AHA's), Salicylic Acid and (especially) Retinoids. These active ingredients are for specific conditions and certainly not for (generally) tween skin (unless prescribed by a qualified practitioner in the case of say, oily or blemish-prone skin)
As stated at the beginning, a gentle cleanser, maybe a little moisturiser if the skin is dry and a good sunscreen.