Teaching measurement in middle school science includes learning the metric system, basic and advanced conversions, and scientific notation. Here are some pro tips to teach, practice, and use those skills all year long.
The Metric System
Forty years ago, we told students that everyone was going to be switching to the metric system soon so they’d better learn it. With a few exceptions (2 liter soda bottles), the United States never really adopted the metric system, marking us as one of only 3 countries in the world (the others being Myanmar and Liberia). Scientists have to use the metric system because science depends on communication between scientists around the world. How does that impact middle school science teachers? Every year, we teach the standard units of meters, liters and grams and every year we insist students use those units in science, and every year they forget and need to be re-taught the year after. Here are some tips to make the metric system more accessible for your students:
- Use it yourself. Give metric units for everything rather than standard units. Display metric units widely – not just their names, but label your bulletin board with its length and width in meters, display a one liter flask or a 400 mL coffee cup with labels. Bring in a 3 kilogram bag of potatoes. The problem with student retention of the metric system is that students never learn to think in metric and can’t picture what a gram is (a nickel has a mass of 5g) or how long it would take them to walk a kilometer (10 minutes).
- Practice. Certainly, do the typical metric system labs of using meters, liter, and grams, but do much, much more than that. Practice with task cards in those odd 5 minutes at the end of the period or while waiting for everyone to catch up. Review, review, review. If you want them to remember it next year, practice it every single day this year – or at least once a week!
Conversions between units is one of the most “mathy” things we do, but it’s an essential skill in science. Students need to be able to convert in single step and multi-step problems. Very often students approach conversions as something to memorize rather than something to understand. My conversions slide show helps students to understand how and why unit conversion factors work and how to decide which conversion factors to use to get to their goal. I added some practice worksheets of varying levels of difficulty to help students, and teachers, determine how much practice they needed.
Teaching measurement in middle school science is one of those skills that a huge investment early in the year pays off dividends over many years. Unfortunately, not making that investment brings a big price in having to reteach the same thing year after year to the same students. This is definitely one of those skills that is best taught five times in five different ways rather than once.