People say it every day without thinking ― “two o’clock,” “six o’clock,” “eight o’clock sharp.” But what is the purpose of that little “o” and apostrophe? Is it short for something? Why do we only use ...

Educator Ruth Mork teaches kids about clocks — from sundials to cuckoo clocks to roosters. Ruth Mork introduces clocks of all kinds — sundials, candle clocks, hourglasses, cuckoos, even a rooster! She ...