We suggest students work in pairs.

Make Sure You Have Space

We suggest doing this activity on the floor. If Bumper Jumper is played on a table the marbles may roll far away if they fall off the table.

We suggest building the Bumper Jumper apparatus where it will be used. Moving the apparatus can affect the connections and how marbles travel. If the Bumper Jumper must be moved after assembly, do so carefully.

Plan Your Time

This entire lesson with the activity will likely take more than an hour. There are two natural stopping points during the activity ⁠— the first one when students finish building their Bumper Jumper apparatus (after step 11) and a second one after they complete their first set of experiments (after step 22). If you are pressed for time or have a short class period, we recommend splitting this lesson into shorter sessions that might work better for you.

Marble Must-Haves

We strongly recommend using “regular” size marbles (14 mm).

IMPORTANT: All marbles used by a group must be the same size/weight. If two different size/weight marbles are used, the results of the Bumper Jumper game will be significantly altered.

Prep Your Materials

Count out 5 full-length label stickers for each pair of students. Then cut the rest of the label stickers in half. Each pair of students will need 5 half-length label stickers. If label stickers aren’t sticking well enough, Scotch tape can be used instead.

Take half of the Dixie cups and place 4 marbles into each one. Distribute these during Step 12 of the activity.

Cut or tear aluminum foil into a small (about 5" x 3") piece. Distribute one piece to each pair of students in Step 23 of the activity.

We suggest students work in pairs. Homeschool students can work on their own, but will need a partner to help with some steps.

Plan Ahead

We strongly recommend pairing this lesson with Lesson 5, “Can you build a chain reaction machine?” If you plan to do Lesson 5, don’t throw away the ramps that your students build in this lesson. Students will use these ramps when creating their very own chain reaction machine.

Classroom Management Tip

Marbles are very fun, but can be very distracting! We suggest waiting to distribute marbles to students until Step 17 of the activity.

We suggest students work in pairs. Homeschool students can work on their own.

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 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.