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19 February 2020

How do I convince my students to sign up for both AP Physics C mechanics and E&M?

On the "Pretty Good Physics" teacher message board - yes, sorry, you must be a teacher to join - a teacher asked how to approach the new signup process for AP exams.  Starting in 2019-20, students must sign up by November (for a full-year course) in order to take the exam.  It's February now, so I know this seems out of date. I think it's worth thinking about now that the October panic of "aargh, should I sign up or not!!!?!" has subsided.

A teacher teaches both AP Physics C mechanics AND E&M.  Completion of the exam is required in order for her students to earn a GPA boost on their transcript.  "Because of the cost," in the past she's allowed students to take either or both exams - even though she covered material and assigned work for both tests in the spring.  But back then, students could decide last-minute whether to pay and sit for the exams.

This year, this teacher worried.  Since students had to register by November... what if they are too scared to sign up for E&M, even if she knows they'll do well?  Even worse, what if the students conspire - "let's sign up for only mechanics, 'cause then we can make teacher skip E&M entirely because none of us signed up!"

She said she needs a plan of what to say to convince students to sign up for E&M - something that's not just "E&M is good for you, it was my favorite course, it'll be yours, too!"

The correspondent is so right, that students are generally risk-averse.  Suggestions about what the teacher personally likes, or what is good for the students, tend to fall on deaf ears - as she suspects.

For those who are teaching APC as a second-year course, I'd suggest following this sequence, teaching algebra-based E&M first, proceeding to calculus-based mechanics, and finishing with calculus-based E&M.  That will start removing the fear of a subject students haven't even seen.  And, this will allay the particular worry that students might try to emotionally blackmail the teacher into not teaching E&M with the whine, "but no one signed up for it!"

I don't like using transactional reasoning, but here it will likely be effective - "We're doing E&M regardless of what you sign up for, so you're being evaluated on that material anyway.  You can only get the GPA and transcript bonus if you sign up.  And I expect that you will do well."  After all, to me the fundamental reason to teach AP is to give students an initial transactional reason to engage.  By the end of the course, they develop a love for physics, an understanding of physics as an end in itself rather than a means to an end.  Yet AP gives us cover while we build expectations and skills in a difficult course - bear with me, because you'll get an extra 0.5 on your GPA and boost your chances of getting into the special college that lets your parents brag to their friends.

Finally, as to the cost of the exam... what do credit hours at a university cost, even a public university?  More than the $94 that an AP exam costs.  Much, much more.  The cost argument is a straw-person.  I mean, obviously it's foolhardy for students to waste money on an exam they won't pass, but isn't the whole point of our teaching to boost the probability that they will pass?  Isn't it the student's job to work hard to make sure they can pass?  If most of the class is failing - which, I must emphatically point out, was NOT the case for this particular correspondent - then something systemic is wrong with the teacher, the students, or the school structure that set everyone up for failure.

There is one possible loophole you might use... Mechanics and E&M are separate courses.  The College Board requires sign-up for full-year and fall-semester courses by November.  However, if your school lists E&M as a second-semester-only course - as on a block schedule - then the sign-up deadline is later.  Talk to your AP coordinator and school registrar if you need to try this.

Most likely, your students will grumble and complain about the early sign-up.  Then they'll just sign up for both exams.  Then they'll be that much more focused on learning all of the content, knowing they're locked in to both exams, that they don't have an out in the spring of their senior year.  Then they'll do well, earn college credit, and be grateful they didn't wimp out.  Sure, there might be a couple of students who don't pass the E&M exam; but they will be far outweighed by those who appreciate your dedication to them, your caring preparation for their college physics weed-out class that they'd otherwise take in a 300-person impersonal lecture hall.

16 February 2020

What is the most important pedagogical skill that physics teachers uniquely need?

I was surveyed by the writers of some pre-service teaching assessment, asking about the most important skills that teachers need for success in a physics classroom.  The survey, written in edu-speak, focused on content objectives and general science practices.

Thing is, the most important skill for physics teachers cannot be measured by a written test.  Do actors audition for Hamilton by taking a test?  "Which of the following does NOT describe the protagonist: (A) Bastard (B) Orphan (C) King of England (D) Scotsman"  "C." "Congrats, you got the part!"  

Good physics teaching is just as performative as musical theatre.  It is a craft which must be taught by example and by sharing tips, which must be learned by trial and error, which must be evaluated by diverse audiences over multiple performances.  

Okay, without reference to assessment or evaluation, then, what ARE the most important skills for physics teachers to know/learn?


Teachers need experience improvising in lab.

That is, firstly they need to know what equipment to get if they don't have a complete set, and to be exposed to new items.

Secondly, they need to help becoming virtuosi at using their equipment.  They cannot be intimidated by probeware, they need to know what a motion detector can and can't do, how to set up a jury-rigged flag through a photogate... in other words, they have to be able to go beyond canned instructions from a "lab sheet".

Finally, they need practice leading lab activities in all styles.  Most physics teachers I meet can set up eight lab stations based on a pre-printed lab sheet.  Most are not comfortable creating their own lab activity; most are not comfortable if the activity goes off book.  

In my AP summer institutes, I aim toward the goal of "playing" in lab.  That last day's activity, in which each teacher creates an experiment from scratch based on an AP problem, is the culmination of a week's worth of practice.  Teachers in my institutes all progress significantly toward comfort with improvisational lab work.

It takes the entire week, though, to change teachers' mindsets from following directions to becoming truly creative.  And even then, I've only changed the teacher's mindset; they often report resistance or even outright rebellion from students if they demand too much creative work too fast.  So the teachers next need help changing student mindsets.

I think I do a reasonable job helping teachers in the APSIs that I do.  But I can't work in their actual school community.  If I could follow up with teachers, I'd help them send this message of creativity in lab to their students, colleagues, parents, and administrators.  It's hard enough to get a student to try something without a clear path to perfection and an A; it's made nigh impossible if other authority figures are, usually out of ignorance, sending students a contradictory message.

12 February 2020

US Invitational Young Physicists Tournament 2020 Results

What a weekend.  The thirteenth US Invitational YPT was held last weekend, Feb. 8-9, at Phillips Exeter Academy in New Hampshire.  Fourteen teams, representing four countries and six US states, made plans to attend; due to the coronovirus, the three teams from China could not attend.  

A Young Physicists Tournament consists of "physics fights," simulations of scientific conference peer review. In preparation, all the teams solve the four problems listed here.  In each round, one team presents their work on a problem.  Questions are then asked not by judges, but by another team.  A jury evaluates both teams based on their ability to carry on a conversation about the problem which demonstrates their deep physics knowledge.

The first day consisted of five rounds of physics fights, followed by the keynote address.  There, tournament director Tengiz Bibilashvili of the University of California Santa Barbara described his personal journey through 24 years of YPTs - from his university days in Soviet Moscow, to leading Georgia to an international championship in 1993, to founding the US Association for Young Physicists Tournaments in the mid-2000s.  Tengiz concluded his talk by awarding his namesake Bibilashvili Medal to his former students in the Sambelashvili family, members of which were serving as jurors this year.

On Sunday midday, finalists were announced: The Nueva School of San Mateo, CA earned the top seed.  

Final results:

2020 USIYPT champion: Cary Academy (NC)

Second place: The Nueva School (CA)

Finalists: 

  • Phillips Exeter Academy (NH)
  • Rye Country Day School (NY)
  • Phillips Andover Academy (MA)
  • Woodberry Forest School (VA)
Clifford Swartz Trophy (poster session champions): The Harker School (CA)


Fifth Place with Bibilashvili Medal: Pioneer School of Ariana (Tunisia)

Fifth Place:

  • Deep Run High School (VA)
  • Episcopal High School (VA)
  • UG School (Georgia)
Teams from China who planned to attend but could not (and we missed them):
  • Shenzhen Middle School
  • Qingdao No. 2 High School
  • Vanke Meisha Academy
At the Sunday night pizza party, the teams each gave Captains' Awards for best poster, best report, and best questioning.  Later on in the evening students from multiple teams packed into hotel rooms to watch movies.  One coach pointed out that Sunday night was when the stories were shared between teams of last-minute experiments, of confidence and trepidation, of the beautiful struggle that is scientific research - a struggle we all took part in.

The 2021 tournament will be hosted jointly by The Science House at North Carolina State University, and Cary Academy.  It will be held January 30-31, 2021.  If you'd like to participate - either as a juror or by bringing a team - please contact Greg through a comment or through email. 

Historical participants may be found through this link.