A motivated child without a teacher could learn to tell time and make his or her own learning clock from the Trivetts' directions. However, unlike Srivastava (above), the Trivetts don't stop to wait for readers to catch up or catch on. Arithmetic is tossed in parenthetically: ""'40 minutes past eight' can be called '20 minutes before 9' (Notice that 20 + 40 = 60)""; ""Because there are four fifteens in 60 (4 x 15 = 60), we say that it is 'one fourth' or 'one quarter' of 60 (I 5 = I [4 of 60)."" And their method of tacking on an exercise in fractions (""Can you make your clockface say. . . 1/20 before 8?"") only complicates the lesson. Most children just learning to tell time will require some backup from a teacher with more patience than the Trivetts, who seem to be racing through their presentation with a sense of time running out.