Any xmas present ideas for 11 years old boy and girl?

I am looking for Christmas present ideas for 11 year old twins , my nephew and niece. She is into crafting, drawings and fictions books. Her parents will get her dragons and dungeons starter kit as a present. My nephew likes playing on computer, legos, history and math.

He has more than enough legos so i though probably legos won’t be a good idea.

Please help with some ideas.