Lesson Summary In this lesson, students build a simple, working motor out of inexpensive materials.  They learn to troubleshoot and to gain confidence in their manipulative skills.  This lesson provides a conceptual transition from the spinning compass motor of Lesson 13 to the more sophisticated motor investigated in Lesson 14 and 15. Teacher Background The first working motors were built in the 1830’s and performed only limited amounts of work.  They were fascinating devices that incorporated automatic switching so that the motor would run by itself as long as electricity was supplied to the electromagnet.  Today’s motors still operate on the same principles. In Step 2 of the Final Activities in Lesson 12, students were challenged to think about ways to switch on and off automatically the electricity flowing through the coil.  In this lesson, the motor they build uses automatic switching, but how it works will not be obvious.  What happens is that the bouncing of the coil, as it spins, interrupts the flow of electricity and provides an automatic on/off switch that causes the coil to keep spinning.  Do not expect all of your students to understand this immediately.  One purpose of the next several lessons is for students to develop a concept of how a motor works.  You will have an opportunity to assess their thinking about this in Appendix A, the Post-Unit Assessments. Set-up/Management Tips Prepare the materials for distribution.  You may want to enlist the aid of students in cutting the sandpaper and wires into the dimensions specified in the materials list.  Information on how to make and repair alligator leads is given in Appendix F.  This activity could be incorporated into the lesson. Make copies of Activity Sheet 5 for the whole class. For each group, make a transparency of Activity Sheet 5. Overhead markers will also be needed. Optional materials include poster board or big paper for each group to present their results. You may need to review how to construct a graph. Decide how you plan to conduct this “conference”. It can be small or elaborate, depending on the amount of time you would like to spend. This is a nice time to incorporate art into the unit if you have the time to spend. Literacy Support Scientific Vocabulary The following words are key vocabulary words that will be introduced in this lesson and reinforced throughout the unit: No new vocabulary introduced this lesson.