4 Proven Ways to Spot AI Mistakes in Your Classroom
Last week’s look at the PISA device myth ended on one finding worth a second look. Students taught to check AI output outperformed students who used AI to write their drafts. Same tool, different job for the student.
That finding raises a practical question. What does it look like to teach a Year 5 class to check AI output on a Tuesday afternoon? Most advice stops at “teach critical thinking.” That gives you a goal, not a lesson.
AJ Juliani’s recent piece, Teach the Frontier, offers a sharper starting point. Every serious plan for keeping AI honest assumes someone has the knowledge and judgement to say “that’s wrong.” By 2040, those people will be the students sitting in your room right now. Here are four ways to start building that judgement in a primary classroom.

Way 1: Build Knowledge Before You Check AI Output
Start with the step most AI advice skips. A student has nothing to check an answer against without knowing the topic first.
Daniel Willingham made this case long before chatbots arrived. Critical thinking, he argued, is not a free-floating skill you teach once and apply everywhere. It depends on what you know about the subject in front of you. In other words, a student who thinks critically about fractions might be helpless with a question about volcanoes.
Picture a Year 4 HASS class asking an AI tool about the First Fleet. The answer says the convicts settled at Botany Bay. A student who has studied the unit knows the fleet moved on to Sydney Cove. A student who hasn’t will copy the error into their book, neatly and confidently.
Juliani puts it plainly: judgement sits on top of knowledge. As AI tools get more capable, background knowledge matters more, not less. For this reason, a knowledge-rich unit is your first and best protection against AI errors.
Way 2: Plant an Error, Then Check AI Output
The simplest place to start is an AI answer you have checked yourself. Before the lesson, run a prompt, read the response, and make sure it contains one or two errors. Some will appear on their own. Otherwise, edit one in.
Run the prompt yourself rather than handing students a login. Many AI tools set age limits above primary school. The Australian Framework for Generative AI in Schools also asks schools to protect student data. Displaying the output on the board avoids both problems.
For example, ask an AI tool to explain to a Year 5 student how to compare decimals. Then plant a classic misconception: “0.25 is bigger than 0.5 because 25 is bigger than 5.” Tell the class there are two errors, and give pairs five minutes to find them. The misconception you plant is often the one half the room already holds. As a result, the error hunt doubles as a diagnostic.
Way 3: Rerun the Prompt to Check AI Output
Next, run the same prompt twice and put both answers side by side. Ask students one question: where do these answers disagree?
Disagreement is a signal. If one answer gives a river’s length in one figure and the second gives another, at least one is wrong. Students then go to the atlas, the textbook, or a trusted website to settle it. That trip to a second source is how students learn to check AI output.
Even so, teach the other half of the lesson too. Two AI answers that agree can still both be wrong, because they come from the same tool. Agreement tells you the tool is consistent. Only a source outside the tool tells you it is right.
Way 4: Make One Question a Routine
Juliani asks his own children one question every time AI gives them an answer: “How would you know if it was wrong?” His hope is that one day they ask it without him.
That repetition is the point. A routine question works the same way as the higher-order questioning you already use, except students eventually take it over. It also pushes back on the problem we covered in the AI confidence trap. AI tools tend to agree with the user, so students need a habit of disagreeing with the tool.
- How would you know if this was wrong? The anchor question. Ask it every time.
- Where else could you check this? Name a source outside the AI tool.
- Does this match what we learnt in class? Sends students back to their own knowledge.
- Which part sounds sure but shows no evidence? Confident tone is not proof.
- What did it leave out? A harder one for Years 5 and 6.
Print the list as a bookmark or a poster near the board. In practice, the first question carries most of the weight. The other four give older students somewhere to go next.
Keep Most Tasks AI-Free, and Say Why
All four ways share one condition. Students need plenty of work where AI plays no part at all. Juliani’s advice is to keep most tasks AI-free and to tell students the reason. The hard thinking stays with the student, because that thinking builds the knowledge they will later check AI output against.
This links straight back to productive struggle. A student who hands the hard part to a chatbot skips the struggle, and skips the learning with it. Telling them so is honest, and most Year 6 students will follow the logic.
The Framework backs this up. Guiding statement 1.2 asks schools to teach students how AI tools work, including their limitations and biases. Statement 1.4 asks for AI use that supports critical thinking rather than restricting it. Statement 1.5 asks every task to state clearly whether AI belongs in it. The four ways above give you a classroom version of all three.
- Week 1: Teach the content. No AI. Tell students why.
- Week 2: Plant two errors in an AI answer on that content and run the hunt.
- Week 3: Rerun one prompt twice and settle the disagreements with a second source.
- Week 4: Hand pairs a fresh AI answer and the five questions. Step back and watch.
Your turn
Try the planted-error hunt with your class this term. Which error did your students catch first, and which one slipped past everyone? Tell us in the comments.
References
Australian Government Department of Education. (2023). Australian framework for generative artificial intelligence (AI) in schools. education.gov.au
Juliani, A. J. (2026, September 18). Teach the frontier. Next Gen Schools. ajjuliani.beehiiv.com
Juliani, A. J. (2026, September). What the PISA results really show us about technology and curriculum. AJ Juliani. ajjuliani.com
Willingham, D. T. (2007). Critical thinking: Why is it so hard to teach? American Educator, 31(2), 8–19.







