Substitute Lesson Plan: CS Fundamentals — Course E

Lesson 1: Sequencing in the Maze (Chapter 1: Ramp Up)

Objective

Students will be able to:

• Order movement commands as sequential steps in a program.
• Modify an existing program to fix errors ("bugs").
• Break down a long sequence of instructions into the largest repeatable sequence.
• Predict where a program will fail.
• Reflect on the debugging process in an age-appropriate way.

Materials

• Code.org Course E, Lesson 1 puzzles (online, via Code Studio)
• Student journals (one per student) — used for warm-up discussion notes and wrap-up prompts
• Debugging Recipe – Student Handout (if copies are available; otherwise reference the debugging steps verbally, as described below)
• Computers/devices with internet access for each student or pair

Warm-up (~5 min)

1. Gather students' attention and explain today they will practice sequencing and debugging in an online maze activity.
2. Ask students to think about a problem they've had to solve in everyday life. Pose these questions aloud (no need to collect answers, just discuss briefly):
3. "How do you fix something that isn't working?"
4. "Do you follow a specific series of steps?"
5. Introduce the key idea: "Some puzzles today have already been 'solved' for you, but they don't work correctly. We call these problems 'bugs,' and your job is to 'debug' them."
6. Quickly introduce vocabulary (say each word and have students repeat it):
7. Program – an algorithm that has been coded into something a machine can run.
8. Programming – the art of creating a program.
9. Bug – an error in a program that prevents it from running as expected.
10. Debugging – finding and fixing errors in programs.
11. Explain the debugging process in simple terms: "Try the first step — did it work? Try the next — did that work? Keep going step by step until you find where it breaks. That's your bug. Then fix it!"

Main Activity (~25 min)

1. Pair students up for Pair Programming (two students per computer if possible).
2. Explain the etiquette for helping a partner or classmate:
3. Don't sit in the classmate's chair.
4. Don't touch the classmate's keyboard or mouse.
5. Make sure the classmate can explain the solution out loud before you walk away.
6. Tell students: "Before asking a teacher, ask at least two classmates for help."
7. Have students log into Code Studio and begin Lesson 1: Sequencing in the Maze puzzles.
8. As students work, circulate the room to:
9. Encourage students who are stuck to ask their partner or a nearby group first.
10. Remind students to use the debugging process: "What is it supposed to do? What does it actually do? What does that tell you?"
11. Reassure frustrated students that frustration is part of learning and persistence pays off.
12. If a student is still stuck after asking peers, ask leading questions to help them spot the error themselves rather than giving the answer directly.
13. Keep an eye out for any student who seems completely stuck or unwilling to continue — check in with encouragement.

Wrap-up / Exit Ticket (~10 min)

Have students take out their journals and respond to the following prompts (written work, can be shared aloud briefly if time allows):

1. What was today's lesson about?
2. How did you feel during today's lesson?
3. What kind of bugs did you find today?
4. Draw a bug you encountered in one of the puzzles.

Collect journals or have students keep them for the teacher to review later.

If Time Remains

• Have early-finishing pairs go back and try to solve any puzzle again faster or with fewer blocks, focusing on finding the "largest repeatable sequence" in their solution.
• Ask students to turn to a neighbor and explain, in their own words, what "debugging" means and describe one bug they fixed today.