Solar cells produce direct current electricity when the Sun is shining on them (or if they are close to a bright light). They do not have to be “charged up”. Nor do they hold a charge. When light photons strike the solar cell material, a flow of electrons is produced instantaneously, and that electricity can be used to power electrical devices such as motors, lights, and buzzers. When the light stops, the electricity stops. Electrical energy is measured in watts, with amperes of current flowing between voltage potential differences. So voltage times amperes equals watts. Volts x Amps

Most Classrooms have a Globe. These usually have the planet correctly inclined (to show its tilt of spin in relation to the plane of our orbit around the Sun), as well as a small plate on top, at the North pole, marked off in hours. For children to visualize where their planet is in a year, in relation to the Sun, it is useful to work with a model. A shared experience makes the learning easier. This could be perhaps a weekly class focus…where is the planet today in its orbit around the Sun? To model this is relatively easy.Pretend the Sun is

In almost any Dollar store you can find an inexpensive birthday card that plays the “Happy Birthday” tune (or some other) when you open it. If you remove the works and remove the battery, you can hook up a solar panel as shown. The panel shown is 1.5 volts. (If using 1 volt panels, you would need two in series to provide enough voltage to make the speaker work.) After removing the battery, use one alligator clip to clip together the contacts where the small piece of card slipped in and out as a “switch”, and attach the other clip to one of

Solar panels produce direct current electricity – a flow of electrons in one direction. Changing the direction of the flow of electrons will reverse the motor’s spin direction. This can be an interesting thing when you connect two solar panels to the same motor, but with their test leads reversed. That is, with one panel having a positive lead attached to the same motor pole tab as a second panel’s negative lead. And on the other motor tab, the situation is reversed – so that the first panel’s negative lead shares with the second panel’s positive lead. The solar panel receiving the most

Gather three smooth black stones, as like to each other as possible. Outdoors, in the sunlight, place the stones on a piece of cardboard. Leave one stone uncovered. Cover one stone with an upside-down jar or clear drinking glass. For the third stone construct a simple test house with a 1-litre (1 qt.) and a 2-litre (2 qt.) milk or juice containers. You will also need Kleenex (or shredded paper towel or dry sawdust or cotton batten) as insulation, some clear plastic wrap, and an elastic band. Cut the top from each carton, about 10 cm (~ 4″) up on from the bottom

Activity: Children build a two-dimensional model of our planet with Sun shining on it, rotating in Space, and relate their planetary position during that rotation to the 24 hours of our clock.Materials: construction paper, paper fastener, cardboard, paper, glue, marker, protractor.Directions: On a large sheet of construction paper or cardboard have the children make an appropriate Sun image in Space.To make an ‘Earth”, here I’ve found an image on-line with the North pole at the center, and glued it onto a circular piece of cardboard. But students could as well draw their own Earth image.Students will probably put the sun and planet in

This exercise lets children directly feel the energy in sunlight. A dowel shaft can be attached to a motor with a piece of tubing slid onto a motor shaft bushing (or the motor pulley mounted backwards, as shown here). Hold the motor and shaft loosely in your upturned palm, with the tubing slightly bent. With your other hand aim the attached solar panel toward the Sun. The motor and shaft assembly will vibrate in the open palm of your hand – a primitive sun-drum. Consider that the solar panel is about 12 – 15% (1/8) efficient, and the motor is about 50% (1/2)

To track the Sun and record its passage was another project that seemed worthwhile. It is tricky for children, or anyone for that matter, to perceive that it is our planet that is moving relative to the Sun, rather than the Sun moving relative to the Earth. Our language is riddled with this false understanding of Earth-centrism. And while it is true the Sun is also travelling through Space, and the Earth travels with it in a spiral pattern, rather than the flat circular orbiting we were taught, it is best not to complicate things at this point. SunTracker with compass,