Hands-on Activity: NXT Ball Shooter

Contributed by: GK-12 Program, Computational Neurobiology Center, College of Engineering, University of Missouri

A LEGO MINDSTORMS NXT 2.0 robot car.
Copyright © Wikimedia Commons http://commons.wikimedia.org/wiki/File:NXT_mindstorm.jpg


This activity helps students understand how a motor in a LEGO® MINDSTORMS® robot uses electricity produced by the battery to move a robot to do useful work in the form of throwing a ball. Students relate the concepts of electricity and battery to the movement of the LEGO NXT motor and connected links. **Note: This activity uses the retired LEGO NXT robot which is no longer available for purchase.
This engineering curriculum meets Next Generation Science Standards (NGSS).

Engineering Connection

Engineers design a wide range of electrical circuits for various electronic devices that we use everyday. Through this activity, students see how an electrical circuit is important for the flow of electricity, which ultimately powers electric devices. In the activity, students design a program to perform a particular task, which helps to cultivate in them a basic understanding of how robots can be operated via programming instructions that drive the motors.

Pre-Req Knowledge

Students should have completed the What Is a Robot? lesson to introduce them to the LEGO NXT robot and the basics of its programming.

Learning Objectives

After this activity, students should be able to:

  • Explain that energy from the battery is converted from chemical energy into electrical energy, electricity, which is used to run the motors of the LEGO NXT robot, which convert electrical energy into mechanical energy, thus making the robot move.
  • Program an NXT robot to move its motor so that it shoots the balls from the ring attached to the motor.

More Curriculum Like This

How Does a Robot Work?

This lesson introduces electricity, batteries and motors using a LEGO® MINDSTORMS robot. The associated activity guides students to build a simple LEGO set-up and see the practical implementation of the concepts discussed.

Elementary Lesson
What Is a Motor and How Does a Rotation Sensor Work?

Students learn about electric motors and rotational sensors. They learn that motors convert electrical energy to mechanical energy and typically include rotational sensors to enable distance measuring. Students create a basic program using the LEGO® MINDSTORMS® interface to control a motor to move a...

Brain is a Computer

Students learn about the similarities between the human brain and its engineering counterpart, the computer. Since students work with computers routinely, this comparison strengthens their understanding of both how the brain works and how it parallels that of a computer.

Middle School Lesson
How Does a Touch Sensor Work?

Students learn about how touch sensors work, while reinforcing their similarities to the human sense of touch. They look at human senses and their electronic imitators, with special focus on the nervous system, skin and touch sensors.

Educational Standards

Each TeachEngineering lesson or activity is correlated to one or more K-12 science, technology, engineering or math (STEM) educational standards.

All 100,000+ K-12 STEM standards covered in TeachEngineering are collected, maintained and packaged by the Achievement Standards Network (ASN), a project of D2L (www.achievementstandards.org).

In the ASN, standards are hierarchically structured: first by source; e.g., by state; within source by type; e.g., science or mathematics; within type by subtype, then by grade, etc.

  • Define a simple design problem reflecting a need or a want that includes specified criteria for success and constraints on materials, time, or cost. (Grades 3 - 5) Details... View more aligned curriculum... Do you agree with this alignment?
  • Make observations to provide evidence that energy can be transferred from place to place by sound, light, heat, and electric currents. (Grade 4) Details... View more aligned curriculum... Do you agree with this alignment?
  • Apply scientific ideas to design, test, and refine a device that converts energy from one form to another. (Grade 4) Details... View more aligned curriculum... Do you agree with this alignment?
  • The development of technology is a human activity and is the result of individual and collective needs and the ability to be creative. (Grades 6 - 8) Details... View more aligned curriculum... Do you agree with this alignment?
  • Describe how new technologies have helped scientists make better observations and measurements for investigations (e.g., telescopes, electronic balances, electronic microscopes, x-ray technology, computers, ultrasounds, computer probes such as thermometers) (Grade 5) Details... View more aligned curriculum... Do you agree with this alignment?
Suggest an alignment not listed above

Materials List

Each group of two or three students needs a LEGO MINDSTORMS NXT kit with software:

The teacher needs a computer with Internet connection and a projector to be able to shows a video to the class.


This activity is part of the How Does a Robot Work? lesson. Through this activity, students implement the concepts discussed in the lesson and come to understand how electricity is crucial for the working of a robot or any electrical device.


robot: A machine that gathers information about its environment (senses) and uses that information (reads program) to follow instructions to do work (acts).

system: A group of interdependent components functioning as a unified whole; a set of methods or rules governing behavior.


Before the Activity

  • Make copies of the Student Activity Sheet on slide 3 of the Activity PowerPoint.
  • Either build the ball shooters prior to class for each group or allow additional activity time for the students to build them in groups.

With the Students


Safety Issues

  • Keep a safe distance from the NXT robots when they are shooting the balls in the ring.


Embedded Assessment: Have students answer the three questions on the Student Activity Sheet (slide 3) as they complete the activity. As a class, discuss their answers to assess their comprehension of the subject matter.


Parker, Dave. NXT Ball Shooter. nxtprograms.com. Accessed 10/26/11. ttp://www.nxtprograms.com/NXT2/ball_shooter/steps.html


Kalyani Upendram; Ajay Nair; Satish Nair


© 2013 by Regents of the University of Colorado; original © 2010 Curators of the University of Missouri

Supporting Program

GK-12 Program, Computational Neurobiology Center, College of Engineering, University of Missouri


This curriculum was developed under National Science Foundation GK-12 grant no. DGE 0440524. However, these contents do not necessarily represent the policies of the National Science Foundation, and you should not assume endorsement by the federal government.

Last modified: November 16, 2018