Explaining that the metric system works in multiples of 10 and introducing the terms and symbols lays the foundation for working with the system. In addition to studying the prefixes "milli," "centi," "deci," "deca," "hector" and "kilo" and their factor numbers, students should gain competence with applying measurement prefixes. Answering questions about the units used to express quantities they encounter on a daily basis -- such as a person’s height, the quantity of milk they drink or the volume of fuel a car tank holds -- makes learning the metric system a relevant process.
On the Discovery Education website, curriculum developer Audrey Carangelo suggests metric system activities such as students measuring their own height in comparison to their friends. Other engaging ideas include finding the biggest classroom in the school building, weighing lunch boxes to find the heaviest and verifying if a carton of packaged fruit juice really contains the amount it claims to hold. Performing these hands-on activities requires simple devices such as measuring tapes, metric scales and measuring cups.
Observing the product details printed on products such as foods, clothing, sports equipment, cosmetics and medicines helps reinforce the concepts of metric units. As a project, groups of students can survey such products at a supermarket, then participate in a classroom discussion on the economic implications of implementing the metric system on international trade.
Researching recipes from different parts of the world helps students appreciate the differences between the American and metric systems of measurement. Converting a recipe provides valuable practice with estimating quantities. The USMA suggests that teachers put students to work measuring portion sizes sold in the school cafeteria in metric units, and following it with a guessing game to reinforce their understanding of the metric system.