I love a good hands on project! The kids were all over this one; they pulled the pieces apart, probed, poked and observed. We've done some work with electrical circuits and simple machines before so they were pretty good at identifying the different mechanisms and figuring out what their function was.
Here, Carter has found the switch that is activated when a pencil is inserted into the sharpener. You can see how it closes the electrical circuit.
This motor actually had two switches on it though. One that is depressed by the pencil, another is depressed by a slide in tray that catches the pencil shavings. The kids found both, tinkered a way to depress both and the motor went wild. We were all thrilled.
Here, they were attempting to rebuild the gear box. I don't think we quite got all the pieces in the right place but I loved how their minds were whirring away during this project. They were so engrossed and pulled up tons of information that we haven't covered in over a year. We all got a bit grimy from the grease and this exploration took up a good portion of our morning but it was worth it. We gleaned a great review session and all of us will always remember what a pencil sharpener's guts look like. Bonus: we now have a motor, a couple of cool switches and power sources to add to our electrical gizmo collection.
Thanks for reading!