US Congress: is it representative? A math lesson

As I read Dan Meyer’s post, “A Response to Danny Brown,” and the stream of comments that followed, I began to think about middle school and the lost interdisciplinary units, or the singular, math related, social justice lesson that “matters”-a topic that appears to be dear to Danny Brown. He writes,

…I really want to model something *important*, in the sense that it *matters*, perhaps politically, or socially, perhaps having a *local* relevance for the students in the classroom

I hope there is still a place in middle school for cross-curricular thematic learning. I haven’t seen many IDUs play out in my 15 years of teaching. Some middle schools are more middle school than others. I only know what I’ve experienced.

The point of my post is to share a lesson I slightly modified from the October, 2015 issue of Mathematics Teaching in the Middle School. I do know one thing about middle schoolers–they always seek fairness.

The proportional reasoning lesson is titled US Congress is it Representative?  Students studying the US Constitution use proportions or percentages to examine equity, fairness, and how the racial and ethnic make-up of our country compares to the ethnic backgrounds of the current Congress.

The lesson begins by providing background knowledge on the US Census, which counts every resident of the US then, from that count, determines the number of seats each state has in the U.S. House of Representatives. The NCTM article did not include this background so this is where I deviated from the original lesson.

The most recent apportionment is below.



If your state lost or gained seats, that would make for good discussion. On a side note, I’m surprised Illinois did not lose more seats in the House!

One major part of the lesson is examining the population statistics and discussing why the sum of the various ethnicities exceeds the total. (The way the Census is counted residents can and do identify with more than one ethnicity.)


Students are then asked, “Based on this data, and the knowledge that there are 435 members of the House of Representatives and 100 members of the Senate, what should a “fair” racial/ethnic make-up of the House and Senate be?

Once they’ve determined what they think is “fair” the ethnic background of Congress is revealed for comparison.


Students use claim, evidence, and reasoning to argue whether the House and Senate are representative of the US population.

I’m with Danny in the sense that I want students to learn about “important” matters. But I also understand that what’s important to a middle schooler may not be the same as an adult.

In my role as math interventionist, I’ll use this lesson to review percentages in our after school math program, but it may get more traction if the lesson is presented by the social studies teachers. So I shared it the social studies teachers instead of the math teachers with the hope they’ll consider it when teaching the Constitution.

Time and timing are the biggest constraints when implementing an interdisciplinary lesson.