My first full-class stop was to the spacious Chemistry classroom on the first floor of AB, where I saw Mr. Rose teach his tenth grade Chemistry class. He was preparing his students for an upcoming lab on determining the density/specific heat of a metal. At first, he demonstrated the complex workings of a vernier caliper as a tool to measure thickness and the diameters of various beakers. However, the magic of this particular lesson was the way Mr. Rose placed the students into the role of working scientists, and asking them to solve the logistical challenges of measuring the temperature of a solid (where a thermometer cannot actually be "stuck" inside the solid to measure the temperature.) There were a number of creative and innovative guesses, and when Mr. Rose finally revealed the secret of measuring the specific heat--by taking the solid out of boiling water, depositing it into tepid water, and then measuring the rise in temperature of the water--there was a collective AHA! moment in the classroom.
Perhaps most significantly, during the lesson Mr. Rose destroyed my long-held and erroneous belief that adding salt to water makes it boil faster. In fact, salt makes water boil at a higher temperature, which makes food cook faster. Alas, for the last thirty years, I've been throwing salt into the water to make it boil faster--to no avail!
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