I quickly realized that although a number of my fourth graders can't tell time (this is an increasingly big problem!), they have some other major misconceptions as well. I saw students who:
--didn't realize the hands moved at different speeds
--didn't understand that there are 60 minutes in one hour
--didn't understand that there are 60 seconds in one minute
--didn't know that there are 24 hours in one day
--didn't know that there are 30 minutes in a half hour and 15 minutes in a quarter hour
Needless to say, Judy and I backed up quite a bit and while I had most of my class working on some problem solving, my "time team" and I got to work trying to build these foundation skills. We counted by seconds. We closed our eyes and tried to guess how long a minute is. We used Judy to "notice" things about our clock (12 numbers . . . 5 minutes between numbers . . . and so on).
We tried doing some skip counting too...like if one hour is 60 minutes, how much is 2 hours? 3 hours? 1/2 hour? Some students were still struggling, so I grabbed some paper and started cutting!
When I used "Judy", students had a hard time keeping track of anything more than an hour so . . .
. . . we started adding and cutting and labeling our parts so that students could start "adding" time. I made up goofy problems like, "Jim flossed his teeth for 30 minutes, turned in circles for 15 minutes, ate cheese for an hour, blew bubbles for 15 minutes . . . how long was Jim busy?" We got to work "building" these times and putting them together to make full hours. The kids had a blast!
I gradually added more time and trickier problems like, "If Caren read for 60 minutes on Monday, Tuesday, and Wednesday and then only read for 19 minutes on Thursday and 35 minutes on Friday, how long did she read in all that week? They IMMEDIATELY said it was too hard and they couldn't do it! I grabbed one of our "hour circles" and wrote 60 minutes on one side and 1 hour on the other. We lined them all up and worked with them almost like they were base 10 blocks! I reminded them that we persevere and, like most math, we could BUILD it.
It was a very busy 40 minutes, but I think we made a lot of progress in our ability to "visualize" amounts of time, turn hours into minutes and minutes into hours, and to add different amounts of time together. Did it stick? TIME will tell! HA! Terrible terrible humor--but stay tuned!
This lesson isn't over yet . . .
As we work into some elapsed time problems, getting a good handle on these concepts is critical! Where are we headed next? THESE!