# That Time I Face Palmed in Algebra 2

It has happened to us all. You have a great idea, scratch that, you have a WONDERFUL idea. An idea for a lesson/activity/warm up that you are so stoked about sleep is difficult the night before. And then, during class, that idea falls flat. So flat that you’re not even sure it has a cross-sectional area. It is the definition of a line with a slope of zero. It hurts. So I’m not going to say this this lesson fell that flat, but we’re talking a slope of 0.125 (1 out of 8 kids understood the task at hand).

The stage for the activity had been set the day before. We had spent the day reviewing how to write the equation for a linear function when given either a slope and a y-intercept, a slope and a point, or two points. The kids seemed to be on top of it. The exit ticket I did had 95% of the class able to do all three. I knew I wanted to try the Desmos Activity Builder that week in class. So I figured I’d give it a shot. The goal of the activity was to have students, while working in pairs, learn how to use Desmos while demonstrating their ability to create the equation of a linear function when given some basic information. The activity then ended with asking students to recall the concept of Domain and Range from the previous chapter to draw one of the letters of their initials using linear equations and domain restrictions.

The concept was okay, the scaffolding was NO WHERE NEAR what it needed to be. The things that I did wrong/the universe did wrong with this first task:

• I introduced too many new things at once. It was our first day using the iPads (new tech for some of my kids), it was our first Desmos Activity, and it was the second day of writing linear equations.
• The Wifi hated us. The school had just upgraded a server (or something like that…I don’t speak IT fluently) and had inadvertently kicked everything Mac related off the network. I had noticed I lost printing capabilities earlier in the week, but didn’t think to check the wifi status of the iPads before beginning the activity…oops. The students weren’t able to stay online for more than 3 minutes at a time and they only had access to the guest network which was running slower than molasses.
• I didn’t set my expectations for their behavior during the activity. What to do if you’re stuck (ask someone else first), what to do if you understand and want to help someone, who to let me know you’re hopelessly lost and need me ASAP.

Fortunately, this mess up of mine was on a Friday. I had all weekend to think about what to change about the activity and how to make amends to my students for causing them a 40 minutes of on-again and off-again frustration. I decided to keep the Desmos Activity platform, but to upgrade a lesson from my early days of teaching: Linear Putt-Putt to an interactive experience. I had written down comments students had made, constructive and otherwise, from the failed activity and tried to do better.

The Upgraded Activity: Linear Equations Putt Putt Desmos Activity

The idea was to give students 4 holes on a putt putt course with a variety of obstacles in their way. Students would need to create 3 linear equations (for a par 3 course) to successful navigate the course and end with a line through the hole. Students were to use domain restrictions to ‘cut off’ their lines so that they represent the path of a ball for each putt. We assumed that the balls would stop where the domain restrictions stopped (I would love to extend this activity one day to have actual angles of impact hold true for hitting a side wall…but we didn’t have time for that).

The things I changed from the Original Activity to the Putt Putt Activity:

• I apologized for throwing too much at them. I realized, in hindsight, that we needed to move slower. I think that this threw a lot of my students for a loop. I think that they had never heard a teacher apologize before, but I asked for forgiveness for the frustration I caused on Friday, and their promise to wipe the slate clean and try a new activity. They agreed and we moved on.
• I gave the students two movable points that they could drag and drop wherever they desired. One point was the ball, and the second point was the “ending” point for their putt.
• This gave students more confidence in creating a linear equation. I heard on Friday’s failed day “HOW am I supposed to GUESS where a line is? I’m not a mind reader! UGH.” on more than one occasion. They had a point, you can tell a student to create a letter on a piece of graph paper because they can create the points that restrict the line…but on an iPad, that simple task is made much more difficult without the use of draggable points.
• I made the points restrict to whole numbers. I’m not against equations being messy, but I was trying to build their confidence, not crush it again. I wanted nice whole numbers for them to play with so that they would feel less intimated by the new online resource.
• We completed the first hole TOGETHER, as a class. I called on students to tell me where to drop the ball, where to move the second point. Then we calculated the slope between the points and created a line together. A student then pointed out how easy it would be to restrict the domain “since we know the x-values for both of the points!” I had her come up to the computer and show us how to restrict the domain using Desmos. We did the same for the remaining two lines and talked about strategies for completing the remaining holes.

This went leaps and bounds better than the first activity. Students were engaged, they were trying to complete the holes under par in order to have a ‘better putt putt score’ than their neighboring peers. I even heard giggling this time around. We had great whole-class conversations about how you would draw a vertical line with Desmos (we had not yet talked about the equations for vertical and horizontal lines). There was even one student who was so intent on having his lines follow the “true trajectory of the ball” that he was googling angle of impact and trying to figure out how to get the slope he would need to have the ball “bounce” off a wall and keep on going so that he only used one stroke instead of two. He opted to use perpendicular lines to represent the bounce, and quickly realized that his method didn’t reflect the real world physics of how a ball would bounce, but he did manage to make a hole in one on the first course using his method. So I’ll call it a win.

The Moral

Some times your intentions are wonderful, but your execution needs a little more work before you unleash an activity on the kiddos. A special thanks to Desmos and the #MTBoS community for taking a look at the Putt Putt activity before I presented it to the kids and for the invaluable feedback that made the activity run smoothly the second go round. Y’all rock!