Today we wanted to plot the points from the Hula Hoop race and find a line of fit. Before school started I saw something that made me go to YouTube and type in “scatter plots desmos” which gave me this video: https://www.youtube.com/watch?v=miiYmGZ2990 After I watched it I totally wanted us to do this with our classes! Luckily there was an iPad cart available so I reserved it for Karen’s and my classes. Wellllll, neither of us got to the iPads, but we did graph the points with our classes, used our ruler to find a line with about half of the points above and half below with the y-intercept of 0 (since if we had 0 kids it would take 0 time)! Then we had them find 2 points on the line that crossed through a grid point on the graph paper, and find the slope of the line. I had been using “delta y/delta x” and doing the subtraction rather than “y sub 2 – y sub 1 /x sub 2 – x sub 1” to make it less confusing, but today I realized if we wrote the 2 points in a table and found the “change in y and the change in x” like we had done with the tables it would be even easier! So I did the points from my line, wrote my equation and walked around – and the bell rang. “Don’t move! You have to find your slope and write your equation and turn in your graph before you leave!” Some look very good, some need a little more work, but that’s what we now know we’ll be doing next week!
Later I looked at a tweet I’d sent myself last night about downloading YouTube videos on my computer from Ramsey Musallam (@ramusallam). I actually like this video a little better than the one in his tweet: https://www.youtube.com/watch?v=q7vOEuGHeGo. It’s really easy to understand and do, because I downloaded the “how to” video from above so we can show it to the kids later. Try it! The only thing you need to do after it is downloaded is to save it where you want it, because it’s in the “downloads” folder on your computer. Finally, I tried putting the points into Desmos and finding a line of fit. My equation was y = 3x + 0, and the Desmos regression line was y = 2.73x + .804. Not too bad! Desmos Picture of Scatter Plot Hula Hoop Data. There were so many cool things today I had to share them.