Students measured the current and voltage of each battery (alkaline and Ni-MH
batteries) and the different diameters of wire (0.32mm, 0.4mm, and 0.5mm). This activity is
a type of scaffold instruction. The reasons for measuring the electrical current and voltage
were not explained to students. Hopefully, students could understand the reason of
measuring ampere and voltage after comparing the differences of the motor designs using
different wires. Furthermore, students discussed the parts of the motor that they needed to
buy. During this time, students engaged in discussion within the group based on the data of
amperes and voltage. Debate is important in sharing thinking and ideas based on scientific
evidence (Hand et al., 2009)