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25 December 2021

Contract grading part 2: How we made it happen at the school level

(The previous post explained *why* I moved to contract grading with my 9th grade AP Physics 1 class. Today I'm discussing institutionally how I worked with my colleagues and my administration to make contract grading happen.  The next posts will discuss how I communicate with parents; and then how I make this particular style of contract grading work on a day to day basis with my class.)

A few years back, a history-teaching colleague presented to the faculty and at an external conference his experience with "contract grading".  His contracts for a required 9th grade course painstakingly listed the descriptive attributes of students who get grades of A, B, and C.  He allowed the students themselves to contract for whichever level best described them.  Then, he held the students to their contract, demanding levels of in-class engagement, paper rewrites, and out-of-class effort commensurate with what the students themselves had agreed to.

My approach is much simpler.  In an AP class, there's no such thing to me as settling for B-level effort.  Students who are good fits for AP physics do all the assigned work to the best of their ability, redo whatever they bombed the first time, engage enthusiastically and diligently with laboratory exercises, and finish all test corrections.  Someone who's only partially willing to do these things shouldn't get a low grade - they shouldn't be in this advanced class to begin with.

On this colleague's model, I proposed to the dean and the headmaster that all of my AP students would contract for an A, by pledging to do each of the items in the paragraph above.  They were quite receptive to the idea, especially as this history colleague had already demonstrated that non-traditional grading approaches neither brought forth the apocalypse, nor a flood of burdensome complaints. The headmaster made the very important suggestion that all students should contract not for an A but for an A-minus, on the grounds that nobody is perfect.  It turned out that this small change was critical to the success of the approach.

We ended up with the contract that you can read here.  

In practice, now, a small committee including the academic dean and the head of admissions select students who they think can handle the AP Physics 1 course as freshmen.  I've asked them to cast a wide net!  That is, they don't just rank by standardized test scores - which they can't anymore anyway since our school's admission process went test-optional.  These folks are all quite familiar with the incoming class.  They make their best guess at choosing a team.

Then, on the first day of class, I explain to the students (orally, and in writing on the course syllabus) that they have been selected for the AP physics section.  In three weeks, I tell them, I'll have an individual meeting with each student.  If by then they've lived up to the terms of the contract so far, and if I judge that they are likely to be successful in the college-level course, I will offer them the contract to sign - at which point they may choose to sign, or to switch into the general physics course.  I remind them that I have chosen them to be part of this team, so that I am invested in their success.  That I will be honest with them if I think they can't handle the course, so that they can just concentrate on each assignment and leave the long-term planning to me.

But what about their GPA?  

Here's what the contract says about grades:

Your marking period report will indicate an (unweighted) grade of A- each term during the year.

After AP score reports are released in July, your transcript will be adjusted according to the scale below.  This will increase the overall GPA for all those who earn 3 or above – which, historically, has been virtually everyone.

However, if your in-class performance is better than your AP score equivalent, your transcript will reflect the in-class performance.

AP Score     Transcript Grade
5             A and honors bump
4             A- and honors bump 
3             B+ and honors bump
1 or 2             B

Note the out that I've left myself and my students: someone who's done well all year won't be penalized for having one bad day on May 9.  That said, the AP exam is pretty darned consistent.  It's rare that someone significantly underperforms what I've seen from them all year.  In practice, my goal is to eventually counsel out anyone whose in-class performance is below the 3 level, so that *everyone* will earn a weighted B+ or better.  Those students who aren't getting 3s on most practice exams are invariably better off building skills in our very strong conceptual physics class, and then returning to the AP course junior or senior year.  

Here's where the headmaster's genius suggestion solved problems I hadn't anticipated.  A student who truly is trying to game the GPA system in the short term is better off with an earned A in general physics than the automatic A- in the AP class!  And a student willing to take a class below their intellectual level for the purpose of earning a higher grade is someone I don't need in AP physics, any more than the football team needs someone who only joined to impress potential sexual partners.  The students who choose to stay - which, so far, has been all of them - understand that they're taking a small GPA hit for now, but in return are freed from the angst of worrying incessantly about whether they're perfect.  

When someone inevitably asks in class about grades or GPAs, my response is gentle, but clear about two points:  (1) Read the contract for details, and (2) If GPA will have any influence on your decision to remain in the college-level section, you don't belong here;  I'm happy to help you switch into the general class, where you're likely to earn a natural A.  They get the message very, very quickly - such that the SECOND student who tries to ask about grades is hurriedly and firmly shushed by classmates.

The next post will describe how I communicate all of the above to parents and advisors.  Then I'll get to discussing the nitty-gritty of how the class works on a daily basis.









22 December 2021

Contract grading in AP Physics 1 part 1: Why I do it.

The most important qualification for success in AP Physics 1 is the want-to barrier.  I mean, yes, there's a level of intellectual horsepower required.  Yet, the borderline students who willingly opt in to the challenge of a college level course tend to do well in the long term, while borderline students who are pushed by parents or counselors - or by the transactional potential of a higher GPA - to take AP physics tend to perform poorly.

Much more importantly, the borderline students who opt in for the right reasons don't bring their classmates or the class culture down.  And such students don't bring *me* down.  Rather, they make me happy.

A number of years ago, I decided I need to limit my work with advanced students to those who truly want to work with me.  I'm sick of fighting with smart students who use my class to game the college admission system.  I'm done with students who have no interest in physics, just in getting a weighted A on their GPA.   I have no patience left for those whose goal is to simultaneously maximize their honors grade while minimizing the engagement necessary to earn that grade.  

My first step was to focus my work on the youngest students.  Our boarding school 9th graders have already made the personal decision to seek out a challenging environment.  They could all have remained at their local public or independent high school.  Already these 14 year olds have shown themselves to be not entirely risk-averse.  They see their teachers as kindly parental figures whose goal is to know, challenge, and care for them.  They *don't* yet see teachers primarily as mean, demanding authoritarians who are obstacles to their success.

Yet, precisely because these barely-teenagers have just taken an enormous leap outside what was comfortable for them, they often don't want to compound leap upon leap.  Our freshmen congregate to the popular activities that their peers say are cool - mostly football and soccer in the fall, rarely theater or the outdoors program.  When we tried giving the freshmen the option to choose to join an AP physics section a few weeks after arrival, many qualified candidates stayed away.  They (and their parents) wanted a "solid start" to their boarding school career.  They were still gaining their footing in discovering who they were socially and athletically - they didn't want to risk "failing" academically.

So, we've gone to a contract grading system in the 9th grade AP Physics 1 class, in which all students in the course get an A- on each term report, no matter what.  After a year of just seven students opting in to AP Physics 1, I've had class sizes of 15, 20, and 20 - out of only 90 or so total 9th grade students at the school.  The students are happy, they're enthusiastic, they're fun to be around.  They're learning physics well enough to pass the AP exam (13/15 passing in 2020, 18/20 passing in 2021, probably similar in 2022.)

I'm sure you have two major questions:

(1) How did I and my school make this happen?  In a school that emphatically publishes grades six times per year, how do I get away with my class being such an outlier?

(2) Without term grades as a motivator, what techniques do I use to keep students invested and engaged for the long haul of a school year?

I'll address each of these questions in the next posts.  




16 December 2021

Describing a laboratory procedure: speed of a cart at the bottom of a ramp

 Samar, who teaches in Maryland, called my attention to a question in the AP Physics 1 Workbook:  

In order to perform an experiment, two students need to determine the velocity of a cart just as it reaches the bottom of a ramp.  In a few short sentences, describe an experimental setup that they could use to determine the [instantaneous] velocity of the cart at the bottom of the ramp.

This is posed as an extra suggestion to discuss with students, and so doesn't have a solution in the teacher version.  Which of course - experimental physics is a creative endeavor, where right and wrong certainly exist, but where numerous correct approaches are available.  

Nevertheless, it's worth me giving a few examples of how I'd suggest answering the question such that (a) the procedure is correct, (b) the procedure is clearly communicated, and (c) the procedure is described in "just a few short sentences" rather than in a multi-page lab report full of vacuousness.

I've graded more AP experimental questions than anyone else on the planet*, so please trust me when I say that you shouldn't accept any response longer than about 80 words.  Seriously - no matter how thorough, no matter how accurate, a long response is no good!  For one thing, the student just used all sorts of time writing all these words here, when that time could have been more productively used elsewhere - on other problems in an exam, or perhaps at home playing with the family dog.  It's not possible to earn extra credit, or a "plus one!" on an AP exam.  Just answer the question, then stop.  If you "lose" a point for not saying something important, well, the extra five sentences you wrote at the end aren't gonna help.

* I'm probably not kidding. Guinness Book, please contact me!

So, how would I answer?  Here are four ideas off the top of my head.  I'm sure others will chime in with other thoughts!  

1. Put a dual-beam photogate above the cart at the position where the cart leaves the track.  Tape a thin slice of an index card to the top of the cart, such that the card breaks the photogate beam.  Then drop the cart down the ramp, and the photogate will read the instantaneous speed at the bottom.

2. Place a meterstick horizontally at the bottom of the track.  Record the cart's movement on video.  Pause the video in consecutive frames when the cart is at the bottom of the track.  The distance the cart traveled between frames - read on the meterstick - divided by the time for each frame (known from the video camera) is the instantaneous speed.

3. Place a motion detector behind the cart.  Have the detector create a velocity-time graph for the cart's motion down the ramp.  The maximum reading on the vertical axis is the cart's instantaneous speed at the bottom.

4. Use a smartcart that can create a velocity-time graph of the cart's motion down the ramp.  The maximum reading on the vertical axis is the cart's instantaneous speed at the bottom.

06 December 2021

Bean Dad and physics pedagogy: they're not the same at all, but I can understand why people have this impression.

I truly hope you missed the brief internet celebrity of "Bean Dad." Brief, tragic summary: a less-than-empathetic parent tried to teach his hungry six-year-old daughter to use a manual can opener by denying her food until she, without help, figured out how to open a can of beans.

Well, true to the spirit of Twitter, it took no time at all for the no-context sweeping generalizations to be pronounced.  I tend to ignore ridiculous Twitter debates that don't involve football, but an author whom I greatly respect jumped in with a barb that hurt: 

"The Bean Dad approach is STEM pedagogy in a nutshell," @jonnysun said.  (He's since deleted the tweet, I think - I found a reference to it, but I cannot find the tweet itself.)

I know other teachers heard similar not-so-flattering remarks about how science is taught.  Folks got defensive about their methodology.  And that way madness lies.

I mean, any good science teacher teaches by inquiry, by modeling, by discovery, or by whatever buzzword means "don't just talk about science, do science".  And none of these buzzword approaches, done correctly, bears any serious resemblance to Bean Dad.

Yet, before we turn our shoulders in a huff... please consider why so many intelligent people think that STEM pedagogy is like Bean Dad.  Fact is, this is a general perception of our craft.  Why?  That's an uncomfortable question.

I know that my very own students have this perception early in every school year. And in my first few years of teaching, I didn't know how to help students and parents and colleagues understand the difference between Bean Dad and "I can't help you with a blank page, I need to see your serious written attempt."  Insisting that students engage authentically with the material rather than demand that I solve their problems for them means that I will always, forever, deal with the charge that I "refuse to help."

And, well... a lot of our peers try to teach via inquiry or the like, but don't really understand what they're doing.  They don't lecture, but in good faith they don't know what guidance to give, just that they're not supposed to lecture.  Or in not-so-good faith they don't care what guidance to give.  Or they assume that since they figured things out on their own, so should their students.  These folks are, in fact, the school version of Bean Dad.  

We're deluding ourselves if we don't acknowledge the existence - maybe even prevalence! - of Bean Dad science teachers.  Their well-poisoning means that everyone else has to work ten times as hard to establish a positive class culture that gives appropriate guidance, but also allows students appropriate freedom to make mistakes.

We can't avoid complaints.  Yet, we can help students, parents, and colleagues understand our methods.  We can be transparent about our pedagogy.  We can de-emphasize the value of right answers and over-emphasize the value of correct approaches.  We can publicly prioritize progress over performance, long-term goals over short-term goals.  We can stand up for colleagues who share our values.  

And we should, must, keep on going in the face of pressure each fall.  When alumni of your course are the ones shutting down the complaints that "Mr. Lipshutz doesn't help us learn," then you know you've done well.