A talking ruler? Welcome to the 21st Century! Crayola's Audio Ruler measures out loud lengths of up to one foot accurate to 1/8 of an inch. To measure, just depress the audio button and roll the device's wheels along any surface. Release the button to hear the measurement!

The Audio Ruler also marks a line in disappearing ink, allowing kids to see exactly where they measured before fading away completely in minutes. The Audio Ruler contains three non-replaceable button cell batteries.