Home Run Kings – Activity Analysis

Earlier this year, I wrote a Desmos activity called Home Run Kings. Here’s the blurb from the activity page:

In this activity, students interpret quantitative data in order to predict whether Bryce Harper—a promising young professional baseball player—will break the all time record for most career home runs.

I like some things in the activity. I’m not so sure about others. I wonder if you’ll help me give it an upgrade?

I’ll start by adding some screen-by-screen commentary. After that, here’s how you can help. Let me know…

  • What you like
  • What you don’t
  • What you’d add/edit/remove

Bonus points if you try this out with students and share a summary of their feedback!

Screen 1

A few words (and an image) to set the context.


Screen 2

I offer students a bit more context (in this case, a graph showing Harper’s home run totals for the first few years of his career) and ask them what they notice. While I’m interested in the full range of responses, I’m expecting quite a few students to focus on the big jump from 21 to 22 years.


Screen 3

Next up, I use a sketch screen to capture informal student thinking about the relationship between home runs and player age. One of the things I love about sketch is that students don’t have to worry about function families, equations, formal domain restrictions, or anything. Just sketch the relationship. (Side note: Don’t conflate formality with richness, here or in other activities. There’s plenty of fodder for rich discussion, uncovering misconceptions, and developing ideas in informal student responses—sketches and otherwise. Of course, building toward formality is a noble goal, but informality is a great place to build from. This concludes my soap box tangent.)


Screen 4

We’ll circle back to Bryce Harper in a moment. But first, a screen to draw out student observations on a pair of graphs showing full (and home run-prolific) careers. The heart of this activity is all about interpreting graphs in context. My hope is that this screen helps move students along toward that objective.


Screen 5

Here I bring Harper back, with five other players’ career totals shown. I’m concerned that there’s too much going on visually on this screen. Would you second that thought? Or push back against it?

Concerns aside… This screen asks students to use the graphs to pick a side and defend their answer. Actually, it asks them to play their own devil’s advocate and construct an argument on both sides. Too much for one screen? Again, I’d love your input here.


Screen 6

The reveal. Not as flashy as some other things I’ve seen online. All I could muster is a screenshot. Any thoughts on how to improve the reveal here? Or does this simple approach serve its purpose?


Screen 7

One challenge I’ve had in thinking through how Desmos activities might play out in other teachers’ classrooms is how best to communicate “Hey, a discussion would be really great right here!” We use teacher tips to that effect. (Successfully? I’m not sure.) But I’ve also tinkered with a discussion-prompting screen like this one a few times as well.


Screen 8

I’ve made a habit of including an extension or two at the end of Desmos activities to allow students who finish a bit earlier to occupy themselves with something related and worthwhile as classmates finish the core part of the activity. And to allow teachers to assign some followup thinking/exploring for home.

I’d love to hear your thoughts on that approach in general, as well as how it plays out in this particular activity. (Though, based on the screen title, it seems I had plans for a second part of the extension that I never got around to building.)


Your Turn

What did you like/dislike? What would you change? Thanks in advance for your comments below and on the Twitter.

Comments 6

  1. It’s a great activity, but I don’t like writing sentences in Maths classes. In a one-to-one setting, e.g. home educators, this could of course be done orally and be finished really quickly.
    I didn’t like the question in screen 2. There’s not much to say. Perhaps it is better to start with a graph showing the number of home runs each year, and then explain why you prefer cumulative data.
    I don’t think screen 5 has too much information.
    You could add some questions about the relation between a frequency bar chart and a cumulative frequency graph.

  2. Post

    Hi Katrin,

    Thanks for stopping by and weighing in! I especially like your suggestion to explore (even if only briefly) the differences (and rationale for using) frequency vs cumulative frequency.

  3. I don’t like the extension screen. It is too much of the same thing, and, if a kid isn’t interested in baseball to start with, the extension would not be compelling. What about using a similar problem but with an entirely different context?

    As for the screen that you thought was too busy, that one was my favorite, because it gave lots of opportunity for students to argue one way or the other.

    In response to the previous comment, instead of having students write their arguments, this could be done as a Think-Pair-Share or small group activity and then different students or groups could be called on to present their arguments.

  4. I think Screen 2 could be improved by using a table instead. On Screen 5 consider adding labels to each of the 5 HR hitters and the era that they hit the homeruns. Have the students pick an argument to make (WILL or WILL NOT). Instead of the reveal being on Screen 6, have students predict how many HRs Harper will have to hit per year by certain ages to break Bonds record using a graph with Bonds & Harper data. Another question to pose with using the 5 HR hitters data is “What four factors do you think contribute to the number of homeruns hit from age 38 on?” One possible extension would be to include a table of players that have the five highest number of HRs hit per year from age 38 to the end their careers. This could add to the prediction of likelihood of breaking the record. I like the idea of the previous comment of an extension on a completely different context.

  5. @mathnerdjet: You’ve touched on one of my lingering concerns about the activity: It’s pretty deep in a context lots of students probably don’t know or care about. I like the idea of a new graph in a different context. I’ll explore that. Thanks for the pushback about the “busy” screen. My instincts are often off. It’s helpful to get a second opinion on these things. 🙂

    @scott: Thanks for stopping by, and offering all these great suggestions. You sparked a couple of ideas for how else I could use this context and data set. I’ll tinker and see where things go. Thanks again!

  6. As a baseball fan, I love it!! But do agree with @mathnerdjet if students don’t like baseball it will be a tough buy-in. I like the idea of a different context for the extension.

    I was also going to add that with the Extension, Rodriguez isn’t playing anymore so that would need a little update already! So many places to go with the predictions and trends.

    What does it say Kris Bryant can do!!?? He already is performing better than Harper as far as HR and BA in his 2 years.

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