DIY Space Invader Mosaic Tutorial by ArtClubBlog here. Lots of 8Bit designs out there that kids could use or they could make up their own. You could add felt to the back and use these as a gift pack of space invader coasters.
This blog is for my crafting alter ego. I did lots of crafts with my very artistic mother growing up and continue doing them with kids now. I love really good kids' crafts that hold their attention and mine.