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Schwartz writes, 2. Don’t tell students what they should know; create the structure for them to experience it on their own. She offers 10 tips for launching an inquiry-based classroom. Her writing is not directed specifically to math teachers but it is easily applied! See her article here!
Then, What do courage, curiosity, and a sense of play have to do with teaching math and inquiry?
Last ... there are websites to help prime your thinking for developing launch tasks to get students thinking about math. One such website is Inquiry Maths. Here is one example of a structured inquiry task from the site:
How do you structure your math class to develop curiosity and promote student questioning?