Saturday, March 28, 2015

Fractions?! Still?!

We are winding down in AP Calculus AB. In our last (flipped) class, the students were practicing area between 2 curves, and I had them do some problems by hand and some problems by calculator. 

Teacher Mistake Number 1: putting the 1st problem as one to be done by hand that involved .... wait for it .... gasp ..... fractions! I had an answer bank (as usual), but in this case, the answers were actually in order. 

Can I tell you that some of my students, though I admire their dedication, were still stuck on that problem for 20 minutes or so, because the fraction adding/subtracting was NOT. WORKING. OUT. We are NOT talking about 31/29 + 441/17 here people. 

We are talking about */4 + */2 - (INTEGER - */16) or something to that effect. Oy! I gently suggested that they may want to move on to some other problems so that they would have a chance to discuss set ups and such, which actually involved calculus, with other students, rather than being all OCD about it and not wanting to move on to the next problem before they finished the first problem.

Note to self: maybe I should have a tiered answer bank for such tortuous, why-does-my-teacher-hate-me type problems: one answer choice for the correct set up, one for the actual integral taking, and then a third for the hideous (51/16) answer!

Another idea: on my IR quizzes, instead of testing calculus-y things for the remainder of April, maybe I should have quick problems such as 1/4 + 1/3 .... or 2/5 * 3/8 .....


  1. You are sooooo right…I suffer with the same thing in my calculus class.

  2. Anonymous8:03 AM

    It's a curse I tell you! We need the Fraction Faries to come make everything better.

  3. Why didn't my comment post? Here goes, again...

    I have a goal of creating a review unit for my Algebra classes that covers operations on integers and fractions as well as number sense, in general. It is going to be entirely digital so the students can access it whenever they need. It will also allow me to give it to my Pre-cal classes as a resource, too. (Not to mention help out when I teach summer school.)

    I'd love to collaborate with any who might be interested.

    Btw, this post from @cheesemonkeysf got me thinking about it.

  4. Anonymous1:18 PM

    I am up for collaborating. Digital sounds cool and useful.

  5. Sweet. Hit me up at

  6. Great blog post, this definitely takes me back to my AP calculus days and I am so glad those days are over. Like your students, I also struggled with fractions in AP Calculus. I so remember distinctively my classmates' faces when a problem with simple fractions was on an exam. It's like they throw us for a loop no matter how old we are. I think it is a great idea for you to quiz your students on fractions, this will allow them to have a a little refresher. And hopefully this will stop the blank stares at your board when fractions are in problems.