Bring to class a scale that displays weight in pounds and another one that displays weight in kilograms. Ask the students to place objects of equal weight on both scales, such as two identical sets of four books, and write down the findings. This activity can help students become familiar with the metric weight of everyday materials and to understand the relation of pounds and kilograms.
A kilogram is too large a unit to measure such light objects as a notebook or a cellphone. For this purpose, the gram, which equals 1/100 of a kilogram, is used. Therefore, a 0.2 kg notebook becomes 200 grams. In the same manner, very heavy objects, such as motor vehicles, are measured in metric tons, with each metric ton equal to 1,000 kg. Give a metric weight value to the students, such as 5.6 metric tons and ask them to convert it into grams and kilograms. Likewise, ask them to convert gram values that you give them into kilograms and metric tons, and kilogram values into grams and metric tons.
This activity will teach students how to examine the metric unit of each value to avoid being tricked by large values, such as 1,000 grams, that signify relatively light materials. Prepare flashcards that contain metric weight values, such as 2 metric tons, 2,000 kilograms and 100,000 grams. Place two flashcards in front of one student at a time and ask the student to answer quickly which value of the two signifies a heavier object or if they are equal.
Draw a number of objects on the board, such as a truck, a ball, a stack of books, a glass filled with water and a chair. Give students several values of metric weight, such as 2 metric tons, 700 grams and 3 kilograms, but don't reveal which value corresponds to each object. Instead, have the students estimate the weight of each object and draw the connections themselves. This activity can help students estimate an object's weight using metric weight values.