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Testing the hearing of babies is not easy, since they cannot tell us what they hear. A health visitor explains it is important to test a baby’s hearing as soon as possible because of the impact any hearing loss can have on speech and language development. The tests are carried out when babies are roughly the same age. They must be easy to administer, not too costly and cause no pain or discomfort for the baby. The distraction test is part of this process. The baby’s attention is attracted by a toy and various sounds are made behind the baby to distract it. If the baby is distracted and looks around for the noise, this generally indicates the baby can hear.

Students could be asked to design a hearing test which they could conduct on their classmates. They could discuss whether these are fair tests, and consider if any other variables could alter the results.

Students could also explore the structure of the ear. They could be shown diagrams and learn that there is an outer, middle and an inner ear. They could make a model eardrum to explore how sound travels through the air. A piece of plastic wrap could be tightly wrapped over a large bowl or pot to represent the ear drum. A handful of rice can then be placed on top. A loud noise could be made above the model eardrum, such as banging two tin trays together. When this big noise is made the grains of rice should jump on the surface of the plastic wrap. It could then be explained that the big bang produced sound waves which caused the plastic surface to vibrate and the rice grains to jump. The eardrum behaves in the same way, being vibrated by sound waves.