Elapsed Time
Bernice Joyce Henry Edward H. White
1136 W. 122nd. St.
Chicago IL 60643
(312) 535-5671/2
Objectives:
Student will calculate elapsed time, given beginning and ending time.
Student will state the time using a.m. and/or p.m.
Materials needed:
Model demonstration clock (for teacher use)
U.S. map
Time line
Paper plates (for the third grade class)
Poster board cards (5" x 5")
Fasteners
Scissors
Strategy:
I. Teacher will introduce and discuss elapsed time using a typical school
day after eliciting activities and the exact time they take place from
the students between the hours of 9:00a.m. and 2:30p.m.
II. Students will individually construct an analog clock; teacher and
helpers will assist.
III. Introduce the problem: Student entered a contest and has won an all
expense paid trip to participate in M.C. Hammers' Annual Youth Camp
held in San Antonio, Texas. However, he/she must check in at the M.C.
Ranch before noon tomorrow.
IV. List things to be done before leaving and time intervals.
Shopping begins: 2:45p.m.
Packing 7:05p.m.
Cab ride to bus station 9:00p.m.
Luxury charter bus ride from Illinois to Texas 10:15p.m.
Bus arrival time in San Antonio 9:35a.m.
Limousine arrival time at M.C. Ranch ends: 10:30a.m.
V. Demonstrate, discuss and teach using the given problem and list of the
things to be done. Use the individual time intervals for teacher demon-
stration and student hands-on activity showing the actual revolutions
on the clocks. Elicit correct responses from the students and place
on the chalkboard. Upon completion of list, students are to determine
total elapsed time. Point out next day arrival.
VI. Total time and next day arrival time prompts introduction of a.m. and p.m.
through the use of a time line and the scheduled activities given earlier
by the students. Give meanings and relationship to day and night and to
the clock. Class will determine if arrival time is a.m. or p.m. after a
brief discussion.
VII. Introduce small group activity: Each student in the group will select a
time being sure to indicate whether a.m. or p.m. Helpers will record given
times on the sheet entitled Hours and Minutes. Each group will determine
elapsed time intervals on their worksheets using their clocks and their
a.m./p.m. cards. Allow one member from each group to utilize the time line
as a means of verifying the time and whether it's a.m. or p.m.
VIII. Pass out worksheets entitled "Time" and also "Telling Time to the Minute"
as a follow-up lesson or practice.
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