It often occurs to me that teaching and learning have much to do with “pondering”. The word derives from an old Latin word that meant “weighing”, and there’s no doubt that my students and I spend a good deal of time weighing ideas. We’re thinking about academic topics throughout the day, and we often do it as if we are holding ideas in our hands to estimate how much they weigh. When I see a student bowed over a book or a writing project, I often picture a scientific balance scale. The pensive student is placing a thought in one of the pans of the scale, then placing other thoughts in the opposite pan, and then checking the relative heaviness. It’s a precise, particular business, this process called pondering, and – like weighing liquids in a laboratory – it requires the utmost attentiveness. Careless thinking, like careless weighing, always leads to imprecise results. One thought might be just a milligram heavier than another, but that could be the difference between a life-changing idea and a dud. I guess my classroom should be, in a sense, like a meticulously-run laboratory. If my students and I are going to be weighing ideas all day long, there needs to be an atmosphere of exactness and precision in the room. We need to keep in mind that we’re absorbed in extremely sensitive scientific work – that of considering and appraising ideas. Perhaps we should put on our lab coats and shielding glasses when we enter my classroom to begin another session of pondering.