Lesson 5:
The Repeat Loop

1. Explain the advantages of using loops in a program

2. Use iteration (repeat loops) to control the flow of a program

3. Find and use patterns to manage complexity

1. Explain the advantages of using loops in a program

In the second reflection question, check that students have listed reasonable advantages for Repeat blocks, such as improving readability or making code easier to manage.

2. Use iteration (repeat loops) to control the flow of a program

Check for successful mission completion in either of the last two missions of the pack.

3. Find and use patterns to manage complexity

Check for successful mission completion in either of the last two missions of the pack.

• Slideshow: The Repeat Loop

• Repeat block support article

1. How can you tell when a Repeat block will be useful in a program?

Student answers should indicate understanding that repeat blocks are used for programs in which one or more commands are repeated right after each other. Programs that have repeating patterns of actions or movement can use loops to make the code easier to read and write.

2. Why might a programmer use a Repeat block rather than just copy and paste the repeating bits of code into a program?

Student answers may vary, but could include that repeat blocks make code easier to keep track of and understand. Repeat blocks also make it clear exactly how many times a snippet of code is repeated, without need to count up the blocks.

3. If Smart Blocks and Repeat blocks both let a programmer use the same piece of code many times, how do you know which one to use?

Student answers should include the fact that a Repeat block is useful when a programmer wants to repeat the exact snippet of code over and over in a row. In contrast, Smart Blocks are used when the code snippet will be used in different places in the program, or even in other missions.

• Familiarize yourself with the above resources.

• The missions might take longer, either assign it as homework or dedicate next session to complete these missions.

Q1. What does a repeat loop do to the code inside it?

A1. It repeats the code however many times it is set to run.

Q2. What is an iteration, regarding the repeat loop block?

A2. An iteration is the number of times the code will run.

Q3. What happens if you take code that is in a repeat loop of 4 iterations, and put its loop in a loop of 2 iterations?

A3. The code inside the first loop will run 8 times.