I think these Halloween Paper Circuit templates from Makerspaces.com look like a lot of fun. You can download the templates for free, but will need to purchase the other supplies. The instructions are excellent. I plan to try this with my 3rd graders. Once they learn the concept, I am going to challenge them to light up a picture of their choice to encourage some creativity and give them the opportunity to apply what they have learned about circuits. By the way, if you are looking for some other paper circuit projects, here is a post I did on ones that our Maker Club did.