Make the AI ask you three questions first

You don't know what context the model is missing, but it does. End your prompt with an instruction to interview you before producing anything, and the questions that come back ("How long is the lesson? What did they study last week? What resources are banned?") surface exactly the constraints you forgot to state.

In practice

I want a revision lesson on fractions for my Grade 5 class.
Before you write anything, ask me the three questions whose
answers would most change what you produce. Then wait.

• Answer briefly and honestly. One line each is enough.
• Keep the habit for anything non-trivial. For quick jobs, skip it; the overhead only pays off when the task has real constraints.
• Notice which questions recur. They're telling you what your future prompts should include from the start.