Each year I ask students to decorate a card stock Christmas tree with their families using household materials. This is a great way for the kids to display their creativity while spending time with loved ones. I display these trees in my classroom.
This download includes the letter I send home to parents each year explaining the project as well as an 8.5"x11" Christmas tree for you to copy on card stock or use as a tracer.
This could easily be modified for other religions. For example, I have sent home a Menorah in the past for my Jewish students, that way we have had the opportunity to talk about other cultural traditions.