One of the key elements of the Science Bowl competition is responding to questions through the use of a buzzer system. Coaches who have participated in contests that relied on judges to decide which student first raised a hand know how difficult and contentious that can be.
To practice, the two choices are (a) to build your own buzzer lock-out system or (b) to buy one (or more) from a manufacturer. If neither of these options are possible, but you still want to help your students get used to "buzzing in" to answer a question, find anything that makes a noise such as a hand buzzer, a horn, or a bell.
Building your own buzzer system is possible if you have a person who knows enough about electronics to assemble a workable system. Essentially, the device needs to be able to respond when one of eight (or more) students pushes a button in a way that "locks out" slower responses and has a light showing which student pushed the button first. You can find many different methods for constructing a system by simply searching for “Build a Buzzer Lockout System” online.
Commercial buzzer systems include these basic components, but shopping around is advised because prices and available features vary considerably.
One final note is that buzzer systems are not just a piece of contest equipment. They have their use in the classroom as well. Any kind of subject matter that lends itself to quick-answer review can become an occasion for an exciting contest between "teams" in the classroom.
Note: By listing these links, neither ORAU nor the Department of Energy is expressing endorsement of these companies or their products. The links are provided merely to provide options for those wishing to investigate buzzer systems.
The TSB uses the 8 player traditional buzzer system from buzzersystems.com with an integrated timer. You can prepare for the event and learn more about the timer by watching this video: https://www.youtube.com/watch?v=5lUvy8x50a4