If you've got the time, we've got the riddle. And it's time for a riddle about time: How many numbers are on a clock? It begins with the simplest of questions that, nevertheless, has no simple answer.

Mr. Joel Lookadoo, Arkansas's 2020 Teacher of the Year, is doubling as a repairman today. The clock in the schoolhouse is broken, and it's up to him to fix it. Being able to tell time is so important!

Most human children learn how to tell time around ages six and seven — but artificial intelligence still, apparently, can’t parse a clock face. Researchers from Scotland’s University of Edinburgh have ...