Abstract: In an electronic reading device, the bar code of the limit time set for a question to be solved is read with a bar code reader. This limit time data is set on a sub tract timer, which decrements as time passes. The bar code reader is also designed to read the answer bar code for the question. During the limit time, answer bar codes can be read with the bar code reader. Beyond the limit time, however, those codes cannot be read. This encourages the learner to solve the questions within the limit time, enhancing the learning effects.

Abstract: A slidable member having an optical display unit is provided in an electronic timepiece case to be slidable to first and second stop positions respectively. The optical display unit is exposed to the outside of the timepiece case with a larger display area thereof when the slidable member has been slid to the second stop position than to the first stop position. Different data items are displayed on the optical display unit by first and second data supply means when the slidable member has been slid to the first and second stop positions respectively.