Solar Powered Dancing Scarecrow Science Lesson
Over the summer we bought a dancing flower from the Dollar Tree that Ada absolutely loved. Since then it’s stopped moving but we still keep it around as an outside toy. Before we went back to the Dollar Tree last week I had asked Ada what she wanted to get and she told me she wanted a Halloween item for the deck outside and continued on to mention the dancing flower. I knew the season had switched over so explained to her that there might not be any flowers, that she already had two, and other people had also wanted to buy them. When we got to the store I was pleased to find other dancing solar toys and was able to snatch the last dancing scarecrow for her. Later on after she had watched it dance outside I told her she could bring it inside as it was still clean so I could start supper. While peeling potatoes for supper she pulled over a chair, brought over her scarecrow, and hovered beside me. At one point after using her fingers to make the scarecrow dance and the hat and crow to sway she remarked how it wasn’t moving anymore. I said something minor back and almost stopped at that small remark, but then continued and explained why that was.
Do you remember when we were outside and the scarecrow was moving? That was because the sun touches that little mirror (the solar cell) there and the sun makes the scarecrow move. Why do you think it doesn’t move in here? There’s light in here right? How is it different from outside? Does only the sun work to move the scarecrow? You know when you were touching it earlier and it was moving… that was kinetic energy from you! Your arm moved and transferred the energy to the scarecrow, but it stopped moving after you stopped touching it because that energy ran out. That’s the same as when the sun is touching it and making it move outside. When you came inside the sun stopped touching it and it stopped.
During the explanation there were a bunch of “I don’t knows”, but also giggling and “that’s silly”. If your child is older you could go on to explain that other items, like a solar-powered calculator, also have a solar cell yet they don’t need to go outside to recharge as they require less power. The sun gives more energy than our inside lights so items that need more energy, like the dancing scarecrow, need the sun. If the dancing scarecrow had needed less power it likely would have work inside and this toddler conversation would, unfortunately, not have occurred.
If you, or your child, are interested in learning more I’ve looked up other blog posts that explain it in more depth. If you want an engineer’s perspective you can visit Engineer’s Zone – Solar powered motion toy tear-down. Here he uses the typical solar dancing hula girl, provides a schematic of the circuit, tears it apart to see what’s inside, and tests the components with different batteries. If you instead want to see a short video of the Flip Flop Solar Plant in action (one video of the outside of the plant and one of the inside), and read how to fix it when it’s broken you can check out this blog post: TG: Flip Flop (or Flip Flap) Solar Plant. If you want to go for a more detailed view of what’s specifically in the toy, where you might find the parts, their estimated cost, and a probable way to assemble it yourself you can go to this blog post: Solar-powered flapping toy.