Category: Mercy Neighborhood Ministries

Motorized Car!

General Topics: Physics, Engineering, Mechanics, Simple Machines, Electric Energy, Circuits, Electronics, Basic Robotics
Grade Level: 6-8

In this activity, we made battery powered remote controlled cars.


  • During the first session, we explained the concepts behind circuitry and how we were applying it, and started assembling the H-bridge circuit we would use to control the car. This required an extended period of time because the circuitry has to be exact or else the car would not operate.
  • During the second session, we assembled the bodies of the cars, including assembling the axles out of pencils and straws, assembling the chassis out of cardboard, and attaching the laser-cut wheels.
  • During the final session we attached the motors and H-Bridges to the cars and tested them out.

What did we learned?

  • Simple Machines: Wheel and Axel;
  • Mechanics: Torque, Motion, Gears and Motors
  • Basic electronics: Its rules for how it works and why the electricity moves in a circuit.
  • For their cars to work, the circuitry and mechanical components had to be done and assembled in a specific way in order for it to work.

Things to keep in mind for future activities: 

  • Preparedness: kits labeled, with descriptions of the pieces
  • We learned that in order to keep the project moving we needed to break the activity into tangible lessons with fun things in between, like decorating the cars.
  • Redesign h-circuit to be more user friendly. The old design requires two buttons to be pressed with the same thumb but it should be changed to be pressed with one thumb

Making a Marble Ramp!

General Topics: Physics, Engineering, Simple Machines, Kinetic Energy, Architecture, Design, Geometry
Grade Level: 6-8

In this activity we built marble ramps. This exercise teaches students how to plan a design and how to build it, and how gravity, acceleration and momentum affect objects. This is an exercise designed around creativity and problem solving.


The students are given a cardboard base to start, extra cardboard to build their towers to give the ramp its height, scissors to cut the cardboard, stencils to base curves from, construction paper to make their ramps, and tape and hot glue to hold it all together. Because there is no one way to build these ramps, the students have to get creative: do they want a zig-zag slide, do they want a loop-de-loop? Each group gets to choose what they want each of their ramps to look like.

Also, here is how we divided the activity into digestible components in order for the students to grasp each piece of the whole instead of getting lost and losing interest:

  1. Creating simple ramp
  2. Measuring momentum based on angle of descent
  3. cutting out & assembling stencils for spiral ramp
  4. Designing and creating loop
  5. Assembling final marble ramp

What did we learn?

  • Observe how gravity, force, counter force, speed, and mass play a role in the making of our marble ramps.
  • Show that the project can be done with the tools the have.
  • Students learn what works for their ramp and are able to think about what went wrong, and then fix it. 
  • Try complex things.

Things to keep in mind for future activities:

  • Facilitate the process of what it means to work together, for example: each person has a specific job or task, part of a whole.
  • The fun is where the problem is. Allow students who have trouble visualizing, to explore their ideas by making.