Ask students to describe the relationship between inches, feet, and yards. Possible responses will include:
12 inches = 1 foot
3 feet = 1 yard
Ask students to describe the relationship between pounds and tons. One possible response will be:
2000 pounds = 1 ton
Give students some sample problems to complete individually to
review how to work within the customary system. For example, you can
write the following problems on the chalkboard or overhead:
36 feet = ____ yards [solution: 3 yards]
30 inches = ____ feet [solution: 2.5 feet]
5 1/3 yards = ____ feet [solution: 16 feet]
8,000 pounds = ____ tons [solution: 4 tons]
1.5 tons = ____ pounds [solution: 3,000 pounds]
Distribute the Whale Weight Activity Sheet to each student.
Whale Weight Activity Sheet
Review the directions, encouraging students to study the information given.
Give students time to complete the chart and make a generalization. This can be done in pairs.
As a class, discuss the generalization that a gray whale's
estimated weight is about 1,000 pounds, or a half ton, for every foot
of its length.