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Moving Through a City
Lab 2 - Self-Driving Car Obstacle Challenge

Teacher Portal


Materials Needed

The following is a list of all the materials and teaching resources that are needed to complete the VEX 123 Lab. First listed are the materials needed for the entire Lab, including the 123 Robot. In certain Labs, links to teaching resources in a slideshow format have been included. Not all Labs will include a slideshow. These slides can help provide context and inspiration for your students. All slides are editable, and can be projected for students or used as a teacher resource.

Materials Purpose Recommendation

VEXcode 123

To create a project to run on the 123 Robot.

1 per group

123 Robot

To navigate through challenges in Lab activities.

1 per group

123 Tiles

To be used as a foundation for the obstacle challenge.

2-4 per group


To run VEXcode 123.

1 per group

Lab 2 Image Slideshow

For teacher facilitation.

1 per class

Recycled Materials

Recycled materials such as paper, cardboard, and pipe cleaners will be used to make the houses, roads, and obstacles for the city. 

1 set per group, or set up a classroom station with all materials

Environment Setup

  • Organize a space in the classroom for multiple groups to set up their 123 Tiles. 
  • Collect and store recyclable materials for obstacle design in a specific spot. 
  • Hand out materials based on a token system. Each child has access to a specific amount of tokens for materials.


Begin the lab by engaging with the students.

  1. Hook

    Do you know what an obstacle is? Teacher will explain how obstacles are problems in the road, such as a cone or a rock.

  2. Demonstrate

    Teacher will introduce and demonstrate how to play the Motion Game. Teacher will put students in pairs. One partner is the obstacle, and the other partner is the car. The car partner will “avoid” the obstacle. Teacher will demonstrate how a car can avoid by turning or moving forward or backward. Students will practice and play the game with a partner.

  3. Leading Question

    How do you avoid an obstacle when your 123 Robot is in motion?


Allow students to explore the concepts introduced.

Part 1

The teacher will introduce the design challenge. Students will develop an obstacle that the self-driving car (the 123 Robot) could maneuver around given a set of specific code instructions. They will use VEXcode 123 to move their 123 Robot through the course.

Mid-Play Break

The teacher will allow students to ask questions and share stories of debugging and troubleshooting their project.

Part 2

Students will complete the final challenge - to use what they know about motion and force to instruct their 123 Robot to avoid their obstacle twice in a sequence while pulling a trailer behind it. 


Allow students to discuss and display their learning.

Active Share

Students walk around the classroom in pairs as a gallery walk. Some students will continue to work on their projects while other students walk around. Students are encouraged to ask questions or help peers complete the challenge.

A VEX 123 character

Discussion Prompts