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31 March 2019

What if your school doesn't officially offer AP classes?

I'm asked on a regular basis about schools who have decided not to offer any Advanced Placement courses.  This move has been trendy for a while, especially in independent schools.  The relevant philosophies vary.  Some schools want to maintain academic independence, for example allowing history teachers to teach more focused and in-depth classes rather than the survey course that is APUSH.  Some schools want to maintain consistency across disciplines - they might still effectively be teaching, say, AP English Literature but not AP economics.  By calling both courses "honors" classes they don't give the impression that the economics class is less rigorous, less demanding, less intellectual than the English class.  

And then, of course, some schools simply don't want to be embarrassed by getting poor exam scores.  You can't lose if you don't play.

If you're a student or teacher at one of these schools, you might ask:

Can students still take an AP Physics exam?  Absolutely.  The counseling office will know how to sign the student up.  You may have to go somewhere else to take it, but any high school student can sign up for, pay for, and take any AP exam.  Enrollment in an officially labeled AP course is not required.

Can a teacher still teach the AP curriculum, using AP materials?  Of course.  AP-copyright publicly released exams are allowed to be used for face-to-face classroom teaching.  And the College Board can't copyright the laws of physics.

Can a teacher complete a course audit?  Yes.  One outcome of a successful course audit is to allow the school to use the College Board trademark "AP" on transcripts, websites, etc.  But such use is not required.  My school is a no-AP school, yet I have submitted and passed course audits for all AP physics courses.  My administrators understand that signing off on the course audit doesn't compel them to use the name AP; it doesn't make me or my school beholden to the College Board.

Can a teacher access the released international exams that are not publicly available?  Well, only if the teacher submits and passes a course audit.  That's why I complete an audit, even though my courses aren't labeled AP - I want access to the wealth of non-public released AP Physics 1 and 2 exams.

Can you just email me those non-public exams so I can use them in my honors class?  No, sorry, I can't.  They may not be emailed.  Them's the rules.  :-)

How can I get them, then?  I'm not sure, other than to complete a course audit.  If anyone connected to the College Board can answer this better, please post a comment.

Can a teacher still be an AP reader?  Sure - I am.  My understanding is that qualifying to be a reader is done by teaching an AP course or equivalent - that's why professors and grad students are eligible.  If you're not sure, just apply.  When you're asked for the number of years experience teaching an AP-level course, count any course that's college level, including dual-enrollment, including a college level course that your school labels as "honors".  Be honest... but let the powers that be decide whether you're qualified.  Don't sell yourself short.

Hope this helps... more questions?  Post a comment!






18 March 2019

Just the facts - capacitors for AP Physics 2

I'm teaching an independent study AP Physics 2 and AP Physics C - E&M this trimester, to just a few strong and highly motivated students.  So much of my work consists of constructing "fact sheets" for each topic.

I've started with topics common to both the AP2 and APC exams - electrostatics, magnetism, and circuits.  I've already posted algebra-based magnetism facts here, and electrostatics facts here. Then general circuits facts are here

But I don't think I've ever posted capacitor facts.  Here you go.  The only Physics C extensions, then, are for RC circuits - I have facts that also talk about inductors and LR circuits, but I'll post those some other time.


Capacitors
Capacitors store charge.  The amount of charged stored is Q = CDV.
Capacitance C is a property of the capacitor.
In the special case of the parallel plate capacitor, its capacitance is
The energy stored on a capacitor is 

In a circuit...
·        *  capacitors block all current after they’ve been fully charged.
·        *  An uncharged capacitor initially will act as a bare wire.
·        *  The equivalent capacitance of several parallel capacitors is their sum.
·         * Capacitors in series add inversely (like parallel resistors) to their equivalent capacitance.

When capacitors are disconnected and reconnected, note what stays the same:
    • If a battery is still connected, the voltage must remain the same.
    • If a battery is NOT connected, total charge must remain the same; however, check the signs of the plates to see if some + and - charge will cancel out.
    • The capacitance is a property of the capacitor’s structure, and will only change if the area of the plates, the distance between the plates, or the dielectric material is changed.

12 March 2019

Jacobs Physics Podcast Season 2, episode 3: rotation

Today I discuss the rotation problem on the 2018 AP Physics C mechanics test.  Note that parts (b) through (e) are, verbatim, appropriate for AP Physics 1 - so even if you don't teach calculus-based physics, listen anyway!

Digressions include:

* Communicating with parents, but keeping their noses out of our students' assignments;
* Teaching students to be brave, not perfect;
* Why memorizing equations means so more than just memorizing equations (including diseases which have modern anecdotes);
* What form should an answer take? Do I need to simplify?
* How integral calculus is like the First Order.

Listen via this link.  Enjoy! 

08 March 2019

Culture building: an alternative to mixed messages about college admission.


Regular readers know that I spend a significant amount of professional energy building culture for my classes.  It's not useful for physics - or any class - to be perceived by students as a means to an end, as a game to play in order for the winners to earn the prize of high grades and college admissions.

At a meeting about revising the school's extracurricular-hours-based community service requirement, I strongly encouraged that we concentrate on culture building in this realm as well.  A community service requirement has the opposite effect than we intend if students game the system trying to find merely the most convenient or least burdensome manner of finishing their required hours.* The vast majority of students talk openly about how to arrange community service such that they check off the school requirement with a minimum of effort.

*Or if well-connected parents can simply arrange easy service hours for their kids, while the students from less well-connected families spend an hour on logistics for every hour engaged in service. 

Just as they talk openly about the path of least resistance to a high GPA and admission to a high-status college.

After the meeting, a colleague got to thinking... "That contractual, transactional relationship we have with students," he said.  "I wonder in what ways we [teachers] behave that might indicate (for better and/or worse) it benefits us?"

In my early days teaching, I know I reinforced a transactional relationship with students.  Fact is, teenagers resent being herded into rooms where adults - too often adults who are not as smart or as talented as they - use their authority to demand that the teenagers do what the adults say.  When I was not much older than the students, and when I was newer to the school community than the students themselves, I felt like grades and the college transcript were my only tools toward ensuring short-term cooperation with my long-term mission to teach physics.  I sympathize with young or new teachers grappling with leadership issues.  I sympathize with young or new teachers who merely use the same carrots and sticks that their teachers used with them.

For experienced teachers, though, I think it's important that our every word, our every action, demonstrate the higher purpose for which we and our students are striving.  I didn't take this job so I could give students privileged to attend a high-class boarding school an even bigger leg up in a rat race.  My classroom mission, aligned with my school's mission, is to promote intellectual thoroughness through the study of physics.  The skills and evidence-based attitudes to which my students are exposed will serve them and society at large in the long term, whatever professional path each student eventually takes.  (And I know that I'm on-track with this long-term mission because a large and diverse number of my alumni have shared with me that they have been well served by my class.)

So what steps can we take to avoid reinforcing a transactional relationship?  Start by considering typical conversations with students.  What do we, formally and informally, praise our students for?

In December, both my school and the national zeitgeist* were abuzz with colleges' early decision decisions.  Who got in to where?  Who was rejected?  How can those rejected folks deal with their failure?  Who should have done better?  Who should we congratulate now that they've been admitted to Stanford?

* that is, Twitter

AARRGH!  With the best of intentions, teachers all over my school and my country were further embedding the notion that our students' worth is in large part measured by the perceived status of the college they attend...  that the primary purpose of school is to secure high-status college admission... that the purpose of a teacher is as an ally - or worse, a hired servant - toward grade, test score, and college status maximization.

Teachers generally understand that college admission is largely a crapshoot.  Seemingly ideal candidates are often rejected; often of two students from the same high school, the one with the perceived lesser resume is admitted.  Teachers see a broader picture of hundreds of students each year, all of whom continue to live full lives regardless of whether they are admitted to their first-choice college.  I have never, for example, heard anyone over the age of 25 lament that their life turned for the worse due to college rejection; rather, these folks tend to say "go state!"  Yet students and their parents still measure their worth by their personal result in the college admissions jungle. 

Consider the unintentional messages sent when a teacher says, "Congratulations on getting in to Stanford!"

The student who got in feels validated, and perhaps a bit smug.  He or she achieved a goal!  Um, is that really the goal we want to praise, winning an admissions lottery?  When we know damned well that it's truly a sorta-random lottery?  

And what about those didn't get congratulations?  What about the student whose friend is receiving praise for admission to Stanford while they got rejected, or while they were admitted to their first choice of James Madison University?  (Or the student who has carefully and consciously decided not to attend college?)

The teaching community is sending conflicting messages, and don't think students don't notice.  On one hand teachers say "your worth isn't defined by college, if you were rejected, that's okay."  On the other hand, teachers repeatedly and publicly fete students for admission to high status colleges! That sounds exactly like coaches who pay lip service to how everyone is an equal part of the team, but then focus all their attention on the starters while never talking to the bench players.  As a bench player, I knew where I stood* with such coaches.

or rather, where I sat

I mean, I know it's a big deal to each individual student when the college acceptance is finally there.  And I don't object to those teachers who want to celebrate a student's acceptance to college as they would a coming-of-age ritual.  It's socially normal to congratulate students on their first communion, bat mitzvah, getting their drivers license, turning 18 years old... 

My real objection is less "congratulations on receiving your college acceptance, this is a life event!"  and more "ooh, Hannah, you got into Yale, you must be so smart and accomplished! And Ashley, you're going to VCU?  Is that, um, a community college?  Anyway, back to Hannah and Yale!"  

My personal approach to culture building is that I don’t discuss college admission with my students.  Instead I discuss, and praise them for, concrete accomplishments.  And if a student was in fact admitted to Stanford, there must be numerous other impressive, earned accomplishments that I can recognize instead. 

"Julie, I saw the school musical last week - your performance was outstanding."  "DeQuece, congrats on the all-time school receiving record."  "Javon, I've heard great things about that podcast you started."  "Palmer, I really liked your presentation about your semester in Italy."  These students are hearing praise for something of authentic value to our current school community - not that an admissions committee pulled their name out of a hat of applicants with similar backgrounds, but something that their teacher noticed and cared about.  Something specific they've earned through their dedication, talent, and effort. 

Chances are, throughout every particular student's time knowing us, we teachers will naturally and organically find some concrete accomplishment to praise, something unique to that student - thus our praise becomes special, personal, meaningful.  And if you do want to congratulate a student on their life event of college acceptance, you can make the congratulations personally applicable to them - as my colleague Pete suggests, something like "Oh, congrats, you're headed to North Carolina next year!  Do you know yet what you'll be studying?  Will you be playing trumpet in the pep band there as you did here?" 

When alumni come back for their 10th or 20th reunions, I want them to remember that I went to their ballgames, their plays, their speeches; that I worked just as diligently to teach and build relationships with their peers with B's as those with A's; and that I effectively and passionately taught them skills that served them in their future pursuits, especially if those pursuits involved physics somehow.

I don't want them to remember me merely as the guy who wrote a college rec that might have gotten them in to Princeton.


04 March 2019

Jacobs Physics Podcast S2 ep 2: 2018 AP Physics 1 problem 3, torque on a spinning disk

This week we discuss an AP Physics 1 question involving rotational motion graphs, N2L for rotation (or the rotational impulse momentum theorem), and a qualitative-quantitative translation.

Jacobs Physics Podcast S2 ep2.

Digressions include:

* Teaching angular kinematics without "teaching" angular kinematics;
* Moving on with your class, even if students are still getting things wrong;
* Dealing with "no fair, we never covered a question like this in class";
* teaching the qualitative-quantitative translation
* Mail Time!

If you have a question you'd like featured in Mail Time, please leave a comment on this post, or email me directly.  Enjoy!

01 March 2019

Advice for a student who has issues with written communication: The Blank Canvas

A participant in one of my workshops asked me about the AP Physics 1 exam and a possibly dyslexic student - a student who can explain answers to AP-level questions well orally, but whose written communication is suboptimal.  Their handwriting is difficult to read, and occasionally doesn't make sense; when they write  equations they tend to skip a lot of steps and work all over the page, making it difficult to follow the organization of their solution.  What advice do I have?

Great question, one I've encountered a number of times.  Please understand that I am not a trained psychologist or brain expert; I speak merely from considerable experience and observation.

Firstly, know that the AP readers are pretty danged good at interpreting handwriting.  Misspellings and messiness are not insurmountable impediments to communication.  

But nonetheless, strong written communication is non-negotiable - AP Physics is not about getting the right answers, but about explaining and describing the concepts which underlie the natural world.  

I've helped students think of their responses to physics questions less as a sequence of mathematics, less a sequence of words and sentences, but more as a free-form exercise in written communication on a blank canvas of paper.  In fact, I demand that students use unlined paper for their assignments, in order to encourage them not to stay inside the lines, in order to encourage them to use the available space in creative ways.

For example, I'm regularly asking students for annotated calculations - in each step of a calculation or derivation, explain in some words the rationale behind the step.  This isn't done in a rigorous format, but rather with all sorts of circling, arrows drawn to the important variables, reference to diagrams and charts... Some students' work certainly looks more organized than others, of course, but a student with the difficulties you describe can practice using alternate - i.e. graphical or representational - means of communicating their own organizational approach. 

Similarly, when a solution starts with a representation such as a free body diagram or an energy bar chart, words and equations can supplement the concepts explicitly referenced in the diagrams, helping the reader follow the argument that the student is trying to make.  The response to a physics question can become as much like a studio art assignment as a physics problem... written communication matters, written communication is non-negotiable, but "written communication" can take many forms beyond merely words and equations.

I've occasionally encountered a student whose doctor has requested a typed-response accommodation.  I'd strongly recommend AGAINST such an accommodation as exactly the opposite of what will help students in physics.  (So many learning-disabilities accommodations presume a 19th-century style sit-listen-take notes-memorize-recall class, which is 180 degrees from a well-taught physics class.) Rather, I think making the most of the blank canvas of a paper and pencil is exactly how to help this student communicate.  Typing in physics is extraordinarily limiting.  When I write this blog I too-often feel like it takes me ten times as long to communicate a simple idea via keyboard as it does in my class with a whiteboard.

As an example of how I might teach the use of a blank canvas for AP physics problems take a look at this solution from a recent in-class test.    Take a look at how the response is more than merely sentence-sentence-sentence or equation-equation-equation.  This student you describe won't immediately be able to create this same type of response, but (s)he can take a look at the multiple styles in there, and can hopefully expand their vision of the ways in which they can communicate physics in writing.  You can start such a student off with some simple practice: "Okay, for tonight's problem, I want you to draw arrows indicating where the work for each step in your derivation has gone."  "Now tonight, draw those arrows again, but this time write words explaining each step."  "Start tonight's problem with an energy bar chart... then write words showing how you knew to draw each bar representing each form of energy."  

Good luck... I hope this helps.

greg