Finger lights were a big hit in stockings last year - lots of fun had on Christmas morning, though I don't generally like bits of plastic tat. I feel something equally transient, possibly light-up, would be a fun distraction again. Stockings (5 & 8 yo) will have an orange, personalised nutella, juice, choc coins, cereal bar or similar, Lego mixels, books, some polished stones or geodes or fossils, stickers and a small thing from the Christmas list.
What random but fun thing should I add?