The company that designed IBM's now makes hardware that uses radio signals. But that unit's hefty price tag kept it from catching on, he said. The new system employs infrared signals. The price drop had a major impact on sales. In the past five months, eInstruction has sold about 100 units, Ward said.
Users span the gamut, from elementary schools and high schools to junior colleges and universities.
N.Y. Dougherty bought a radio-signal model, which eInstruction continues to produce. He prefers it over the infrared systems because infrared can easily get blocked by obstacles in its path. A student seated directly in front of an infrared beam, for example, can keep it from reaching its target. The new system has a built-in safeguard to combat this, Ward said. An electronic class roster tells the teacher when each student's answer has registered.