What are the high-level questions that students need to answer?
Consider the questions you want students to be able to answer as a result of the lesson's instruction and practice. Keep your unit questions in mind since the lesson-level questions will likely be steps towards answering those overarching questions.
Question stems are a powerful way to push students thinking. While the first three levels of Bloom's (as seen below) are considered lower-level, the question stems in those levels can be used to scaffold student thinking.
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