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Loops inside programs

move right
repeat 3 times
move down
collect the star

Before, during, after
A loop can sit in the middle of a program. The robot still reads from the top. Lines before the loop run first. Then the loop runs. Then the lines after it.
```
move_down()
repeat 4:
    move_right()
```
Count every move
Line 1 moves the robot down 1. The loop moves it right 4 times. 1 + 4 = 5 moves in all.
move down
repeat 4 times
move right

Watch the robot
Here is that program as blocks. Tap Run the program. Down 1, then right 4. The robot lands on the flag.
```
move_up()
repeat 2:
    move_right()
    move_right()
say("Done")
```
Two lines inside
A loop can hold more than one line. Both indented lines repeat. Two rights, 2 times, makes 4 moves right. say("Done") is not indented, so it runs once.
```
move_up()
repeat 3:
    move_right()
```
Make it shorter
Three move_right() lines in a row can become one loop. Keep move_up() before the loop. The loop gets the number 3.

For parents

Goal: Your child learns to read programs with lines before and after a loop, in the right order.

Ask: which lines are inside the loop? Which lines run only once?
Count the moves together: the moves before, plus the loop moves, plus the moves after.
In the labs your child guesses where a program ends and builds programs with lines before and after a loop.

Away from the screen: Play a game: stand up, then repeat 3: hop, then sit down. Ask your child which part repeated and which parts happened once.

Coding · Loops