1) Thanks for the replies Simon.
2) Depending upon the students knowledge and testing equipment available, some good questions to ask would be:
A) The rotation of the motor (clockwise or counterclockwise)
B) If the students and/or the teacher has experience using a voltmeter, they can measure the initial voltage of the batteries and/or the amperage upon the motor startup. For a brief second upon start-up, the motor will have a higher amperage. Once the motor is spinning, the amperage will level off. They can also notice the battery voltage will drop a little upon the motor start-up.
C) Voltage of the Motor will be DC due to the use of the batteries
D) Are the 2 batteries wired in parallel to form 1.5 volts or are they wired in series to form 3 volts DC? From a visual perspective, and once again if the students have knowledge of how batteries are wired, they can easily look at the batteries and determine if they are wired in parallel or in series.
E) Have the students explain that the fan is allowed to run by first converting electrical energy from the batteries and then converting the electrical energy into magnetic energy which the motor converts magnetic energy into mechanical energy which then converts the mechanical energy into wind energy of the fan.