Repeat count
Run the commands a fixed number of times.
Topic Guide
Loops and Repetition
Loops repeat a group of commands. The programmer chooses what repeats, how often, and when it stops.
Why this matters
A game checks for collisions many times each second. A robot keeps reading its distance sensor. Putting that work in a loop makes the repeated rule easy to see and change.
Beyond this topic
A traffic signal repeats a cycle, but it cannot simply flash every light at once. The sequence, timing, and stopping rule are part of the loop.
Math and logic
Forever
Keep running them while the project is active.
Repeat until
Check a condition and stop when it becomes true.
Iteration
One trip through the loop.
Small examples
Snowball wave
Launch each hazard after a controlled delay.
Animation cycle
Repeat costume changes at a readable speed.
Robot patrol
Move along the route and check for obstacles each time.
Countdown
Subtract one after each timed interval.
Program connections
Where this topic appears.
Active now
Scratch & Game Design
Students author games, animations, simulations, and strange interactive stories while learning how events, rules, and state fit together.
Active now
Robotics
Students write commands, wire simple circuits, read sensors, and trace physical cause and effect through the Sense–Decide–Act loop.
Coming later
Roblox Studio / Lua
A possible later step from visual programming into Lua, 3D objects, events, and larger game rules.
Common mistakes
Accidental forever loop
The program never reaches the blocks beneath it.
A condition that never changes
The repeat-until loop has no way to finish.
Copied blocks
One timing change has to be repaired in twenty places.
No pause
The loop runs so quickly that the result cannot be seen or controlled.
Put the idea to work
Scratch & Game Design
Guided Project
Attack of the Angry Snowballs
Defend a mug of cocoa from falling snowballs. Each wave gets faster, and winter becomes less reasonable.
See how it works
Robotics
Computer Lab Project
Robot Patrol Challenge
Design a repeating patrol that notices an obstacle, tries a response, and checks whether the response worked.
See how it works
Scratch & Game Design
Guided Project
The Floor Is Definitely Lava
Build a one-room platform game with a controlled jump, safe platforms, lava, and a clean restart.
See how it works