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Moving Through a City
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The Moving Through a City Unit will familiarize you and your students with the concepts of motion and force while also practicing foundational concepts of computer programming. Students will use VEXcode 123 and the 123 Robot to sequence commands and make the 123 Robot move and complete various challenges.

What is Sequencing?

Sequencing is the order in which commands are executed, one after another. An action or event leads to the next ordered action in a sequence. Sequencing is important so students can program their 123 Robot correctly.

  1. Move forward one space
  2. Turn right
  3. Move forward two spaces
VEX 123 Robot

Students will have many opportunities with their 123 Robot, to create programs that use sequencing to achieve a goal.

What is Project Planning?

Project planning allows students to write or verbalize code before testing it, in order for students to gain immediate feedback on the sequencing process. This helps in the initial planning of a project by creating the logical framework and sequence of code. By learning to plan how the project could be completed, students can easily communicate their solutions to others.

Oftentimes, students can "guess and check" their way to finding a solution. This, however, doesn't result in them building a conceptual understanding of the coding concepts. The planning of a project helps students to move beyond a surface level understanding of programming, to a more conceptual understanding. Project planning requires that the students think conceptually about their solution before they begin testing it.

What is VEXcode 123?

VEXcode 123 is a coding environment that is used to communicate with VEX 123 Robots. Students use the drag and drop interface to create VEXcode projects that control their 123 Robot’s actions. Each block’s purpose can be identified using visual cues such as its shape, color, and label.

The following VEXcode Blocks will be introduced in this unit:

When Started - runs the attached stack of blocks when the project is started.

When Started Block

Drive for (steps) - moves the 123 Robot either forward or in reverse for a given number of robot steps. Choose which direction the 123 Robot will move, and set how far it will move by entering a value in the oval.

Turn right - rotates the 123 Robot right 90 degrees.

Turn left - rotates the 123 Robot left 90 degrees.

What is Force?

Force is a push or pull on an object. When force is applied to an object, and that force is also unopposed, it will change the motion of an object. There are balanced as well as unbalanced forces. Forces that are equal but opposite in directions are called balanced forces. Balanced forces do not cause an object to move.

An example of a balanced force would be two groups of people playing tug of war with the same amount of force. This would cause the rope to stay in place, since the opposing forces being exerted on both sides is equivalent. However, forces that are unbalanced will cause an object or objects to move.

Tug of War

If both sides are being pulled with the same amount of force, the rope does not move and neither do the people pulling. However, if the pulling force is greater on one side, it will cause the rope to move as well as the people on the other side.

What is Motion?

Motion is movement. This movement can be analyzed by observing and measuring how far an object travels, how fast it moves, and the direction that it moves. Motion is created when forces are unbalanced. This is due to one force being greater than another.

Think about pushing your arm against a wall. The force of your arm is balanced with the force exerted by the wall in order to remain at a standstill. Compare that if your arm is pushing against a balloon. The force of your arm is unbalanced with the force being exerted by the balloon, so the balloon begins to move.

Pushing wall