A 60 minute lesson in which students will explore the concept of mass by comparing and ordering objects.
This lesson contains a link to an external video. Please watch the video prior to presenting this lesson to ensure that the content is appropriate for your students.
Watch the Elephant Mass Song on YouTube. After watching, discuss and define the terms ‘mass’, ‘heavy (er/est)’ and ‘light (er/est)’ with the students.
Compare a solid object (such as a rectangular prism) with a hollow, similar-sized version of the same object. Show how the solid object has more matter than the hollow one and therefore has more mass.
List some objects from the video that were heavier/lighter than the elephant. Ask the class for suggestions on how we can compare and/or measure mass.
Choose two objects from around the classroom and present them to the class. Ask the students which one they think is heavier. Encourage the students to suggest how they could check if they are correct.
Demonstrate how to compare the masses by holding each object in opposite hands and feeling for the greater mass. Share with the class which object is heavier/lighter and explain how you can tell.
Allow the students to take turns to hold and compare the mass of the two objects. Encourage them to share any interesting observations with the class.
Individually, or in small groups, allow the students to collect five different objects from around the classroom and take them back to their desks. Ask the students to pick one object as their favorite.
Encourage the students to compare the masses of the objects using their hands, then arrange them in order from the lightest to the heaviest. Ask the students to write/draw the list into their workbooks. If the students are having trouble discerning a difference between two objects, ask them to replace one of the objects with something heavier/lighter so they can make an ordered list.
Ask the students to look at their favorite object in the list and encourage them to identify an object that is lighter than their favorite. If their favorite object is the lightest in the list, ask the student to identify/think of something else that would be lighter.
On the board, model how to write a comparative sentence e.g. The block is lighter than the ball. Allow the students to write their own comparative sentence for their favorite object in their workbook. Repeat the comparative writing process, this time for an object that is heavier than the student’s favorite object.
Ask the students to share their comparative sentences with three other classmates. Encourage them to describe how they could tell/feel the differences in masses.
Encourage more capable students to look for objects around the classroom that have the same mass.
Assist less confident students as they are selecting classroom objects to compare.
Suggested Assessment Strategies
used strategic whole class or individual questioning
observed student participation during learning activities