• Students will distinguish between matter and energy.
• Students will develop questions about weight in space.
• Students will take the mass of objects and compare them.

Matter can be identified and described by many properties. Mass is a measure of the amount of matter in an object. Mass is constant in all circumstances, whereas, weight depends on the gravity of a planet. In this lesson, students will learn the difference between mass and weight and how to use a scale to measure mass.

Teacher Preparation

Provide a few scales (measure in grams) in stations around the room. Also, provide a bathroom scale for students at one station.

Lesson

Play the video: What is the Difference Between Matter and Energy? Encourage students to listen for the first half of the video. At the prompt, pause the video and allow students to write down what they heard in their Mass v. Weight Lab Notebook.  Press play to continue to the video and encourage them notice the environment.

Using the Mass v. Weight Slide Show, go through the differences between matter and energy. During this discussion, have students identify which parts of the video were matter and which were energy. For example, water, birds and trees are matter, but sunshine and the wind are energy. Have students draw something made of matter. For example: a person, ball or pencil.

Matter can be identified and described by many properties. As you go through the slide show, emphasize that matter is something that can be touched.

One way to classify matter is by mass. To illustrate the difference between mass and weight play the video of astronaut Chris Hadfield at the International Space Station. Point out how everything floats because there is almost no gravity in space. Then, discuss that mass is the same everywhere, but the weight of matter depends on the gravity. For example, a toothbrush has the same mass in space but different weight.

Scale Activity
Allow students to move around the stations you have set up throughout the room with scientific scales and a bathroom scale. They could weigh themselves on the bathroom scale if they choose to, and they should find the mass of different objects on the scientific scales. Emphasize that the mass depends on how many atoms are in the object. Encourage students to record their results in their Mass vs. Weight Lab Notebook.

Tip: To find mass using a bathroom scale, multiply pounds by 453.6. This will give you mass in grams.

If there is time, have students rank their objects from heaviest to lightest.

The Sanford Connection
When athletes use weightlifting to build muscle, it is gravity pushing down on mass that makes them heavy! Learn about Dr. Lisa MacFadden and the science of sports.