Today, I planned and co-taught a lesson to 6th graders about decimals. As an introduction, we had them place some numbers in order from least to greatest – partly to get them working in small groups, and partly to see what we have to work with in terms of what they already know about decimals (having just finished a unit on fractions). Several of them expressed displeasure at this, particularly when confronted with the challenges of deciding whether 0.5 or 1/2 is smaller and where to place 0.3 and 2/3. The complaints centered around things like “I am never going to use this!” “Why do we have to learn this stuff?” and “I will just use my calculator.”
Once we moved further into the lesson, the complaints shifted slightly – the focus of today’s lesson was to practice using benchmarks to estimate sums and differences. Now, the students were upset that they couldn’t just do the math to find the answer – that we were expecting them to actually *estimate*! You know, in case they are ever at the store and trying to decide how many bags of candy they can buy with $5, or whether they can afford that iPad yet….
Tonight, I am sitting at home, enjoying a fantastic fall storm, pondering various knitting related things. The thing I keep coming back to is how useful math has been when it comes to knitting. Decimals and fractions are endlessly useful, and despite what people warn about gauge and precision and accuracy, estimation can be quite handy as well!
So – what mathematical concepts do you use when you knit? Or do you avoid knitting anything that might require even the slightest hint of math beyond simple counting?