Students learn that even great coders make mistakes — called bugs — and that debugging is the fun detective work of finding the one broken step and fixing it.
Students will be able to…
Your program doesn’t work — but the computer isn’t “wrong,” it did exactly what you said. So how do you find the one step that’s off?
Project each buggy program and read it aloud. Have students find the one command that’s wrong — the tool explains how to fix it.
Tap any phase to open the teacher moves and student actions.
A program runs but does the wrong thing — whose “fault” is it?
Teacher models debugging.
Students use the tool.
Students create/fix.
Students share a fix.
Aligned to the ISTE Standards for Students and the CSTA K-12 Computer Science Standards.
Debug (identify and fix) errors in an algorithm or program that includes sequences and simple loops.
Test and debug a program or algorithm to ensure it runs as intended.
Test solutions and troubleshoot to improve them.
Describe steps in a procedure using sequence language.
Preview the three formative checks. Tap “Sample answer” to see what mastery looks like — hide them before you print for students.
Have students write a working program, add one bug on purpose, then trade and race to find each other’s bug. A printable bug-swap card is in the CS library.
Tap a card to flip it, then rate whether you knew it. Built from this lesson’s vocabulary.
A quick self-check with instant feedback, drawn from this lesson’s key terms.
A print-and-go review sheet with a built-in answer key. Tap “Show answer key” to reveal answers, or print the clean version for students.