Cut two 1-by-4 cm strips of aluminum foil. Bend a paper clip into a large loop with two short tails. Thread the tails through the center of a margarine tub lid and bend the ends into small hooks. Drive one aluminum strip through each hook. Set the tub lid on the mouth of a glass jar so the aluminum strips are suspended. Charge a balloon by rubbing it on wool and bring it near the electroscope to test. The aluminum strip leaves should repel each other and rise in opposing directions.
Metal is used as a source of electron emission in many electroscope experiments. Two affordable and accessible types of metal are zinc metal and sheet metal. Always rub metal with steel wool or sandpaper prior to testing to remove any oxides and excess particles. This will ensure the metal is exposed and accurate test results are achieved. Using inflated balloons is an even less expensive alternative to metal. They can also store excess electrons, which cause an electroscope to respond when the balloon is brought near the paper clip.
To avoid interference by charged particles in the atmosphere, connect charged metal being tested in the electroscope experiment directly to the paper clip of the electroscope apparatus with jumper wire. Best results are achieved when the wire section is short and it can be attached at both ends with simple crocodile clips. The direct flow of electrons will ensure more accurate experiment results as movement in the electroscope leaves should be more pronounced and easier to observe.
Photoelectric experiments involving electroscopes will require one or more sources of light, depending on the test's objectives. Inflated balloons will need to be rubbed against human hair, animal fur or a wool sweater to build excess electrons, which will cause electroscope readings in an experiment. Humans can also be a source of charge when they conduct electrons from a statically-charged balloon to an electroscope by touching the paperclip; they can also transfer excess electrons directly from their bodies after rubbing their socked feet across a carpeted floor.