The IEEE have a series of lesson plans for teaching technology. One of them is “Build Your Own Robot Arm”. It uses everyday inexpensive items such as cardboard, paper clips, rubber bands, etc. It teaches students to design within a given set of parameters and specific materials.
We used this lesson in December last year prior to Kick-off and it helped prepare the students for build season.
Here is the link.
http://www.ieee.org/web/education/preuniversity/tispt/lrobotarm.html
Other lesson plans:
http://www.ieee.org/web/education/preuniversity/tispt/lessons.html