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17 February 2011

My Rant: "When are we ever gonna use this?"

9th grade physics student: Mr. Lipshutz, graphing is pointless and we are never going to need this.

Mr. Lipshutz:  You're gonna need it on the exam, so shut up and start studying.

The student who whines about "when are we gonna need this" is really saying "I need an excuse for why I won't learn what you ask me to learn. Here's one excuse that has consistently gotten me sympathy from my parents and teachers outside the science department: If I fail, it's not because I'm a lazy bum, it's because the material isn't useful to me right this instant."

Never mind that American history has no immediate use outside the classroom, never mind that conjugations of être are useless except in the unlikely event I go to Paris, never mind that I'm never going to make a dime just because I understand Hamlet's motivations. I'm going to complain that physics is useless because some adult somewhere in my life (and most of my friends) will validate my intransigence by saying, "That's okay, honey, no one is really expected to understand that stuff, you're right, you're never going to need it. Everyone gets a D in that class."

When are we gonna use this, you ask? Right now, on this pop quiz.


  1. Greg,
    I'd reframe this as an opportunity. I use American History directly when I try to think about the revolution in Egyp. The conjugations of etre are fascinating when we look for the connections Latin, and Hamlet is pretty much the canonical text for getting at the inner life of any angst ridden teenager. More importantly, I use the skills of analysis I picked up from studying all of these topics in high school all the time when I try to read a newspaper, pick up a new foreign language (something I don't do as much as I should) or get into the heads of my students.

    The same is true in physics, if not more so. The right hand rule is a wonderful way to visualize a fairly complex interaction between a charged particle and a magnetic field. My guess is that learning to visualize complex data and interactions will be a pretty valuable skill.

    I try to use the "when are we going to use this question", which comes up a lot in my class as a good challenge to me to see if my students really are seeing the bigger skills I'm trying teach: breaking complex problems down into smaller parts, thinking analytically, etc. I see moments when this question comes up as places where this isn't really clear in my curriculum, and I have some work to do.

  2. Sometimes even the brightest students ask this question (I teach HS math), and I think it deserves an answer. The difficulty is giving them an answer they understand and will accept. The world-view of most HS students is framed by their experience of the world, which is EXTREMELY limited (Result: "This stuff is useless and/or pointless."). The other side of the problem is that students have no clue what they personally will have to do; in fact rarely do they have a clue what their own parents do, So when I say things like "Exponential equations are important for describing processes in medicine and finance," their response is a glib "I'll never be a doctor or a banker".

  3. Greg,

    My response to that question involves elements from what Dan and Quantumprogress have both mentioned. I first tell them that my goal for each of them is to learn critical thinking/problem-solving/analytical skills. Physics just happens to be the vehicle through which that is accomplished. I tell the students that they're correct that they will probably never need to know the speed of a cannon ball fired perfectly horizontal off a tall mountain, with no air resistance, just before landing. HOWEVER, the skills used in solving that problem (i.e. picking out important information, determining the significance of key words such as "fired horizontally", etc.), those problem solving skills may count for something when they go to buy their first car, pay taxes for the first time, understand their cell phone bill, and the list goes on.

    That usually begs the question, why not teach us that stuff instead of physics? My reply may not be the best, but I explain to them the importance of understanding how things move. I also explain how important physics is to technology and how, if they've never had a physics class, they wouldn't realize how much they love (or hate) physics. Bottom line is, this stuff *is* important and they need to be exposed to it at some time and that's why we teach it. -QED <- just kidding