Measure for Treasure
X marks the spot
on drawn-to-scale classroom maps
By Bob Krech
Treasure seekers have always known that the best way to
find a cache of gold doubloons is to use a map — preferably
one designed by an authentic pirate. But these days, good
treasure maps are hard to come by. No problem. Your class
can still experience the thrill of tracking and locating
hidden booty, even in school! Help grades four through six
students work together to prepare for a treasure hunt that
uses math, map, and measurement skills.
Map Share
Using one or more sample maps, take about 15 minutes
to review four of their common features with your class:
title, compass rose, map key, and scale. Point out how the
title identifies the geographical area shown in the map.
Ask a volunteer to locate the compass rose, a symbol that
indicates the directions north, south, east, and west. Next,
ask the students to translate pictorial symbols on the map
by using its key, which is usually found in a small box
in the map's corner. Finally, explain how scale can be shown
on a line that is divided into sections, each of which represents
a larger unit of measure. Tell students, for example, that
a one-inch section on the map can stand for a mile in actual
distance. Have the children take turns in class using the
sample maps to find examples of each feature. They should
also discuss their usefulness.
For homework, ask each student to bring in a map from home,
being sure to ask a parent or caregiver for permission first.
As part of the assignment, tell the children to be ready
to locate and discuss the title, compass rose, map key,
and scale on the maps they find.
Measurement Units and
Scale
At the conclusion of map sharing, focus the discussion
on scale and its purpose. Explain how scale keeps size and
distance in their proper proportion while allowing us to
"carry the world" in the glove box of a car.
Now really ignite enthusiasm for mapmaking. Tell students
that a "hidden treasure" will soon be placed somewhere
in the classroom. To track it down, they will need a classroom
map that is very accurate and drawn to scale. The treasure,
of course, is the incentive to spark a review of the various
units of both metric and standard linear measure: miles,
kilometers, yards, meters, feet, inches, and centimeters.
Have students form groups of three or four to discuss which
units and scale would be best to use. Most classes eventually
decide on scales such as 1 inch = 1 yard or 1 centimeter
= 1 foot.
Make the Maps
Remind students that a good map has a title, a key with
clear symbols, a compass rose showing direction, and a guide
to scale. Provide graph paper (divided into one-inch- or
one-centimeter-square boxes, depending on the scale selected)
on which their maps can be drawn. Make available measuring
tools such as rulers, yardsticks, meter sticks, measuring
tapes, and string.
Children can work together to do the actual measurement
of the room but should keep their own notes and design their
own individual maps. Guide students to measure only things
that don't move by themselves, such as desks, and remind
them that placement and size of furniture are important.
Plan on at least two 40-minute classes to complete the measurement
and mapmaking.
The Dot Marks the Spot
Collect the completed maps. Then ask for a volunteer
who will go out into the hall while you place a small adhesive
dot or marker somewhere in the room. On that child's treasure
map, mark the corresponding spot with an X. Place
the dot in a location where it cannot easily be spotted
(such as inside a desk or under a chair)-insurance that
the treasure-hunter will not immediately see the marker
and so must rely on the map to locate it. Call the student
into the room, hand back the marked map, and send him or
her off to find the hidden dot. Once the child succeeds,
produce a "treasure chest" and have him or her
choose a prize such as stickers or pencils. (Ones printed
with "I Love Math" are particularly nice and can
be found in the catalog published by the National Council
of Teachers of Mathematics. See
Math & Map Resources.)
Have each student take a turn using his or her map to find
treasure, while classmates cheer each youngster on! Even
though they won't find any doubloons, students will be delighted
to find that math can be rewarding!
Bob Krech, an Instructor
teacher-adviser, has been an elementary-school teacher for
23 years. This article was originally published in the March
2000 issue.
