LUMAJANG, EAST JAVA – Rr “Roro” Suindah Wijayanti, SPd MM, a science teacher at SMPN 4 Lumajang, is committed to implementing active learning. "I strive to make students engage in active learning every day. I am also often helped by the paguyuban (parents groups for each class) and the students to meet our needs in learning tools and materials," Roro said.
For example, when learning about electricity, his grade 8 students were invited to find out about the theft of electricity that happens in everyday life. "I link science learning to the context of everyday life to make it more meaningful. Learning activities support scientific literacy as well as aligning with the reading culture movement that has been developed by the school," she said.
During the previous lesson each group of students was asked to record the use of electrical appliances in their homes in general, such as refrigerators, rice cookers, washing machines, lights, and charging cell phones. They were also asked to record how many hours each of these were used for every day.
The lesson started with the discussion of a newspaper article that discussed the theft of electricity and each group brought along some paid electricity bills. They were asked to think and explain about whether there is a connection between the theft of electricity and payment for electricity each month.
The lesson was continued by presenting a picture of a power meter and an invitation to the students to ask questions about matters related to the meter and the electricity bill. Some questions that arose included: Why must every home have a power meter? What is shown on the electric meter? Does the electricity used correspond to the cost that appears on the bills? The students then did the following activities in several steps, namely:
(1) read the electrical power used by the household appliances at home,
(2) determine the price per kWh according to the electricity bills,
(3) work out data based on the names of the electrical appliances, the power they use, and how long they are used each day,
(4) after working out this data and finding the cost per kWh, calculate the cost to be paid in one month,
(5) compare the results of their calculation of the electricity bills to the actual bills from the electricity company.
Students were also asked to look for information to support the results of the experiment in books, on the internet and from staff from PLN (the state electricity company) who were invited to come and answer questions. Apparently, the results of the students' calculations about electricity usage in their homes, showed that mostly the estimated electricity consumption exceeded what is actually paid for. "I found the difference between the usage of electricity and payment amounted to Rp. 26,000," said Irma, a grade 8 student. In fact, there were students who found a difference of more than Rp 200,000 compared to what they paid.”
Students were then assigned to go to the nearest PLN branch to ask a member of staff about their findings. It turned out that the difference shown by the calculations were caused by the subsidies from the government, but there were also some students who admitted that there was some theft of electricity in their homes. Then the teacher gave the students material on the impact of the theft of electricity and about the substantial electricity subsidies from the government. After reading the material, the students were asked to think about the causes, effects, and solutions for these problems.
Another interesting lesson taught by Roro was on the application of Archimides law. She invited students to examine the phenomenon of ships sinking. By using plasticine to make a ship and using marbles as passengers, the teacher asked the students to prove the relationship between the volume of the vessel and its buoyancy according to Archimedes law.
The activity began with the students being assigned to find information from newspapers, the internet, or books related to incidents where ships had sunk. Based on the information obtained by the students, they were then asked to make highlevel questions such as: Did the number of passengers cause the ships to sink? If not, what caused ships to sink? What should be the weight of the passenger load so that ships don't sink?
The next step was for the students to build ships with plasticine. Before being used for this, the plasticine was weighed and put in a bucket of water. At the outset, the plasticine shaped ship sank because it was too heavy. Students then kept reducing the weight of the plasticine until it could float. Then, marbles were placed one by one on top of plasticine shaped ship until it went from a state of floating to sinking.
The numbers of marbles that resulted in the ship floating, drifting, and sinking were recorded by the students. Through this activity, the students proved a test of Archimides law that the less the weight of the object (by reducing the amount of plasticine), the smaller the pressure the object exerts on the water, so the plasticine ship floats. When the ship is loaded with more marbles (analogous to an increase in passengers), the increasing pressure it exerts on the water eventually means it sinks. (Dkd)