In the Science units “The Heat is On!” and “Transformers” grades 6 to 8 investigated the concepts:
“Energy cannot be created or destroyed, only be transformed from one form of energy into another”
“Heat energy can be transferred by conduction, convection and radiation”
“Energy resources are renewable or non-renewable”
“Non-renewable energy resources creates environmental problems and humanity will eventually run out of them”
“For a sustainable future humanity has to switch to renewable energy resources”
During the units the students have constructed solar heaters following the steps of the Design Cycle; Investigate, Plan, Create and Evaluate.
At the end of the units, the performances of the solar heaters were tested in a competition. The rules were simple, all groups started with one liter of room tempered water (21 degrees Celsius) in the morning. In the afternoon the water temperature was measured again, and the solar heater with the hottest water was the winner. The results were very impressive. all groups at least doubled their temperatures:
Trisha, David, Michael and Sophie grade 6
Temperature increase: 51 °C
Anton, Willem, Matthew and Mohammed grade 6
Temperature increase: 48 °C
Macy, Jed and Teja grade 7
Temperature increase: 44°C
Valerie, Michaela and Laura grade 8
Temperature increase: 41 °C
Aysha, Chloe and Claire grade 7
Temperature increase: 33°C
Alex, AbdulAziz, Qatadah and Williams grade 8
Temperature increase: 21 °C
“This project was really fun and educational. We learnt how a solar water heater works and we were very happy when it went all great. If we could do this project again I would redo the painting and we should have use metal instead of cardboard so that it could heat well” – Macy grade 7
“Our group decided to create the solar heater using a box, a reflector and tin foil. First we worked out the measurements and cut out of cardboard the correct size box and reflectors. After fitting the box and reflector, we painted it black to absorb more sunlight” – Michaela grade 8
“First we covered the inside of the cardboard box with glad wrap. This turned out to be not a clever.way of making the cardboard box water proof. After our box dried, we applied alluminium foil to the base instead, and it worked fine” – Valerie grade 8
“We decided to use foam filler to isolate the box. We put the foam filler on the outside box and placed the inside box on the foam filler” -Trisha grade 6
“The funny part was the jokes we made and how everyone at least agreed on a five minute break on double periods to have fun and then work again” – Willem grade 6
“I think our solar heart will be successful, because we have heaps of insulation eg, foam filler, Styrofoam, smaller metal box, bigger cardboard box. I learnt that insulation keeps heat in, dark colors absorb and keep heat, light colors reflect heat, glass keeps heat in, glad wrap also keeps the heat in” – Matthew grade 6
“At first I had a very broad idea about solar water heaters, but with everything that I have learned so far I thought of another good way of making a solar heater: a black plate of steel with rims that are a few centimeters tall, with a cardboard box around the the steel box, with insulation, so that when the heat hits the steel box it will not go straight out of the bottom of the box. The reason I would do this is because black attracts sun, and the cardboard box with insulation around the steel box would be there to keep the suns heat inside” – Sophie grade 6
