We suggest students work in pairs.

Plan Ahead

To complete this lesson, students will need the ramps and levers they built in the previous lesson.

Students can also add a variety of materials to extend their chain-reaction machines. You can ask them to bring things in, or gather some basic materials to keep in the classroom. See the list below for items we recommend having on hand. Or, for more ideas, watch "Inspiration for Chain Reaction Builders" in the Extensions before you start this activity to see some possibilities.

• Extra printouts of the “Chain-Reaction Starter Kit” handout from the previous lesson (in case students want to make more ramps)
• Card stock for making custom-built ramps
• Paper cups to serve as ramp supports
• Books and boxes to add height
• Dominoes or objects that will topple like dominoes (dominoes built of LEGO bricks, cassette tapes, paperback books, markers standing on end, etc.)
• String
• More stickers
• Things that roll (empty cans, toy cars, rubber balls, markers lying down, toilet-paper tubes)
• Unconventional ramps (like empty binders)

Make Sure You Have Enough Space

Each Chain Reaction Machine will take up several feet. Each student or group of students will need a table or several desks pushed together as a work space.

Classroom Management Tip

Marbles are very fun, but can be very distracting! We suggest waiting to distribute marbles to students until Step 14 of the activity.