# Note:

This is a lesson by Dan Meyer. Check it out here.

# The Goods:

- Use this…Desmos Activity
- Celebrity Age Guessing Presentation
- Student Handout
- Desmos Table and Trend Line Template
- Padlet page for student sharing

# The Lesson:

The teacher leads the students through the Celebrity Age Guessing Presentation. The students fill out the handout below throughout the activity. I made a Google presentation in order to easily change the celebrities and ages from year to year.

After the students get all of their data, they will input it into Desmos. See link below.

I included a table and a slope-intercept form equation in order for the students to find the line of best fit. Give the students some time to play with it. Then, have the students compare their equations. All of this provides a good discussion about what a trend line is and why it’s important.

Eventually, the teacher guides the students to find the “perfect guess” line. The class will use this in order to figure out who the best guesser was for the day. This also provides a good opportunity to discuss which scatterplots show the most accuracy. We can talk about why the graph on the left shows more accuracy than the graph on the right.

After having this discussion, the students will evaluate each other’s graphs and vote on which one was the most accurate.

This is where I need some help. What is the best way for the students to share?

I can think of 4 options:

- The students walk around the room and put rankings (1 to 5) on each graph.
- Use AirServer to display student screens on the projector.
- Have the students take screenshots of their graphs and upload them to a class Dropbox account. The teacher can then display the images on the projector.
- A combination of the first 3.

**Update: **Desmos tweeted this great idea:

@DaneEhlert Neat lesson. Have each Ss link their Desmos graph on a @Padlet page. Then add a link to a Google form for voting & total results

— Desmos.com (@Desmos) April 7, 2014

## Padlet Page:

Here is the Padlet page with a Google form.

What did I miss? How can I make this better? As always, I appreciate any feedback.