Images from the website, The Dynamic Periodic Table.  http://www.ptable.com/

Heather

Desmos is not just for math teachers. To support this point, I created a Polygraph activity using elements from the Periodic Table. Eager to field test the Polygraph, I reached out to a few 8th grade science teachers.  Heather Wingo took me up on my offer.

A Desmos Polygraph is run similarly to the games, Guess Who and 20 Questions.  The program randomly pairs up students.  In the pairing,

• Partner A selects an element
• Partner B tries to figure out the element by asking yes and no questions.
• Partner A respond to the questions by pressing the “Yes” button or “No” button.
• For confusing questions, Partner A may respond with the third option, “I don’t know.

I’ve lead multiple Polygraph activities before but this experience stood out for 2 reasons. First, the type of questions students were not what I had expected.  Second, the conversation with Heather gave me insight to improving the activity.

The Questions

Since students studied the periodic table months ago, I provided the pictured reference sheet.

Prior to the start, I set the condition. Students were not able to eliminate an element based on color.

When one student pushed the boundaries and asked, “Is your element blue?”  His partner responded by selecting the, I don’t know, option. This made me laugh.

I then began noticing unanticipated questions, such as

• Is your element used in making a light bulb?
• Is your element a metal?
• Is your element a gas?
• Is your element in group 1?

Eighth grade science teachers reading this maybe giggling at this point.  Or, saying, “Duh.”  Did I take into account the categories such as solid, liquid and gas, metals, nonmetals etc… , when designing the activity?  Yes and No.

There’s a strategy to creating a balanced Polygraph. My design decisions where based on using the symbol, name, atomic mass, atomic number and energy levels to eliminate elements.  Although I did feel states of matter would be another elimination category, I didn’t strategically incorporate that standard into the design.

My Conversation with Heather 

During the debrief, Heather addressed her curriculum in conjunction with the activity. Her points:

1. Students need to know the states of matter (solid, liquid and gas)
2. Students need to know which elements are metals, non-metals
3. Students need to know which groups on the period table contain alkali metals, transition metals, halogens and noble gases
4. Students need to know how to read, understand and identify parts of a periodic table

The activity I presented addressed point 4. She wanted to scaffold questions to include a discussion of points 1 – 3.  Our solution was to create a second Polygraph focusing on the states of matter, and the various types of metals and non-metals.

Closing Thoughts

This was my first time field testing an activity in Heather’s classroom.  As in every field testing situation, I walked away with more information that I walked in with.  I enjoyed listening to Heather share her content knowledge,  expectations of students and ideas for improving, or in this case creating a complementary activity.