Every year, the students in my class participate in the Invention Convention. Each student invents something and puts together a display board with the information. The kids had a blast and learned a lot about design process and the steps to inventing an item. We even made business cards and conducted on-line patent searches. Everything was done at school with the exception of building the prototype! If you have not tried a project like this, you may want to try it! It is well worth the class time!