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Break down the action into a series of steps to enhance the cause-and-effect nature of what seems to be one event, like charging the electroscope. This will give you an opportunity to ask students what is happening, the sequence of actions, and most importantly WHY things are happening. It might be a good idea to make copies of the accompanying explanation titled How the Electroscope Works to give to your students. Require them to explain what is happening in each picture and why it is happening. But the electroscope drawings on the board the next day and have volunteers explain them to the class without consulting their explanation sheets. Let the class catch and correct any mistakes after each student’s presentation. Then erase the charges from the diagrams and challenge a student to fill them in and make the correct explanations. This process of questioning and subsequent application of theory will give you a much better assessment of whether students are absorbing the material than administering a short answer test. Students will develop a better understanding and be able to apply that understanding to different situations with this approach. That should be our goal in teaching all science. Despite your best efforts, some students will insist that they have no idea why a neutral aluminum-foil ball is attracted to a negatively charged comb, or why a balloon rubbed on their hair sticks to the wall. Simply remind them that electrons are the charges that move, and that there are only two reasons why anything happens in static electricity, as highlighted on page 2: opposite charges attract, and same charges repel. Then help them brainstorm the answer. Remember to break the action down into steps and stick to the rules, and they’ll discover they DO know the answers. Don’t be concerned with the thought that you won’t be able to tell whether a charge on something is positive or negative. No one can tell the type of charge just by looking at it. You must test it with a-charge you already know ispositive or negative and see how the unknown charge behaves. (For example, glass rubbed with silk always becomes positively charged. And hard rubber stroked with fur always becomes negatively charged.) Remember, charges must follow the two rules above. Either kind of charge will attract neutral objects as well as its opposite charge, and either kind of charge will repel a charge of its own kind. So if an object is repelled by a positively charged glass rod, for example, that object must have the same charge as the rod. If the object is attracted, it must have an opposite charge (or be neutral). Well are you convinced yet? Give this approach a try. Both you and your students will enjoy the experience and learn some serious science at the same time.