In this activity students will learn use sequencing and logic as they guide an agent through a puzzle. They also consider the best path /solution and the universality of their solution (or not).

• Play the Trailblazer game.
• Watch videos on CS concepts of instructions and algorithms.
• Reflect on whether there is more than one solution or a best solution.
  

Trailblazer Activity

Learning how to build a StarLogo Nova model requires students to learn how to translate an initial idea of what the turtles should do into specific instructions of how they should do it. In this activity, students will specify directions to help others recreate the safe path through a tangled maze without ever seeing it.  Later we will draw a direct analogy to the conditional instruction used in programming the same behavior.

Materials needed:  Instructions and playing board.  Red, blue and black pen or pencils.

Print out the activity sheet (playing board) and gather the materials.

How to play: On the map, START at the designated position and heading in the direction of the arrow. Your objective as "Trailblazer" is to draw a continuous path that gets you to all of the pots of gold while avoiding the hazards.  Using a pencil, draw your path through the CENTER of squares. Pick up ALL the gold while avoiding the hazards. End up back where you began at the START position.  Next, go back and color the squares leaving signpost instructions for all that follow you ("The Followers") according to these rules:

Your followers are left with these instructions:

·       Take a step forward.

·       If you are standing on a RED square, then turn right by 90 degrees

·       If you are standing on a BLUE square, then turn left by 90 degrees

·       If you are standing on a BLACK square, then turn right by 180 degrees

Trade your map with a partner (or take on the role of a "Follower") and figure out if following the landmarks you left for "Followers" lead you along the path to collect all of the gold while avoiding the hazards.

New Concepts: Algorithms  and Instructions

Reflections:
Reflect on the Trailblazers activity.  Were you able to accurately follow the path using the signposts you left? Did you make any mistakes (such as forgetting to color certain squares or using the wrong color squares)?  Post your reflection to your portfolio in "Reflections->CS Concepts" under the heading "Instructions."

Then reflect on if there is more than one right solution? and if so, how would you decide which solution is best? Post your reflection to your portfolio in "Reflections->CS Concepts" under the heading "Algorithms."