Your teacher will have let a watch with a radioactive face run down, so that the hands are no longer moving. He or she will then put the watch face down on photographic film in a dark room.

After two days, your teacher will remove the watch, wrap the film, and have it developed. Examine and describe the printed picture.

For comparison, your teacher will place different materials, such as paper, cardboard, tinfoil, and leadfoil between the radioactive watch and a unexposed film.

After allowing each material to remain undisturbed for several days, he or she will have the film developed, and you can examine the pictures.

You might be interested in researching the work of Henri Becquerel (1852-1908), a French physicist. Becquerel found that when a sheet of black material was placed between photographic paper and uranium (element 92), a picture would be produced.

He hypothesized that the uranium must be giving off rays that could pass through the black material and affect the photographic paper.

Similarly, you can test other materials such as radioactive rocks.

Your teacher will make certain that you are not given any dangerous materials for any experiment.