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PlayOwl

Coding · Grade 3

Trace, Test and Debug

Third graders trace programs with trace tables, design normal, boundary and unusual test cases, learn four common bug types (off by one, boundary, wrong order, not reset), and fix bugs with a failing test, a trace and a full re-test.

  • 4 lessons
  • About 85 minutes
  • Trace, test and debug check: 8 questions
  • Ways to answer: program with blocks, choose an answer, put code in order, trace code, highlight a text and match pairs
See plans Included with Family, Teacher and School plans. Open in PlayOwl

What learners will discover

  • Trace a program with a trace table, including loops and decisions.
  • Design normal, boundary and unusual test cases with expected results.
  • Recognise common bug types: off by one, boundary, wrong order and not reset.
  • Fix a bug from a failing test and confirm the fix by re-running every test.

Lessons

  1. Trace tables 4 steps2 practiceabout 16 min
  2. Test cases that find bugs 4 steps2 practiceabout 16 min
  3. Common bugs 5 steps3 practiceabout 16 min
  4. Fix and re-test 5 steps3 practiceabout 15 min
  5. Trace, test and debug check 8 questions at the end

Keep exploring

Games to practice with

  • Robot RoutesSnap together arrow, repeat and dance blocks to guide Bolt the robot home.
  • Bug DetectiveA robot program almost works. Run it, spot the buggy block, and fix it.
  • Sorting FactoryTurn a work order into if/else rules and watch the conveyor sort every item.

More 3rd grade coding

Guide for grown-ups