Gather the students around you as you begin the book Chimp Math. This is the story of a newborn chimpanzee whose mother abandons him. The zoo caregivers need to take care of him. They document what is done to help him grow and thrive.
Begin on page nine of the book and learn about how the caregivers feed Jiggs, the chimp. On page 10, there is a timeline of his feeding schedule.
Ask individual students to come up and show the beginning time on the clock. Ask them to advance the clock to the next time while the class counts how many hours have elapsed. Elapsed means how much time has passed between feedings.
Jiggs begins to grow and learn new things. His schedule changes so on page 18 we see a schedule for his day.
Ask students to use their individual clocks to figure out the elapsed times for each of the activities on the chart. For example, Jiggs drank milk at 9:00am and then again at 11:30am. How much time between feedings? Then invite a student up to the classroom clock to show the elapsed time.
Throughout the book, the students will see ways that elapsed time is represented: timelines, clocks, bar graphs, calendars and charts.
Ask students what determines how you represent elapsed time. (Timelines, calendars can show longer periods of elapsed time.)