Meaningful gift idea

My boyfriend loves meaningful gifts/keepsakes. Im wanting my kids to do something/make something for him for Christmas. We aren’t married, we’ve been together for 2.5 years but he has done more for the kids then their actual father has. They are 3 and 6…. I need some ideas that would be meaningful but doesn’t imply as a step dad title if that makes sense. I don’t want to rush or label it.