Rice University logo
 
Top blue bar image
For Math Teachers by Math Teachers
 

Archive for September, 2014


RUSMP Teacher Spotlight: Wilkie Law at Stehlik Intermediate School (Aldine ISD)

September 30th, 2014 by Alice Fisher

A student teacher observed Mr. Law’s classroom, and told him afterwards, “You can tell the kids really like being in your classroom.” Wilkie Law responded, “I think the paramount thing in the classroom is building relationships because you can teach a kid anything. But whether or not they retain it depends on their relationship with you because the relationship gauges the importance of what you’re teaching them.” Wilkie lives by this belief and spends the first two weeks of school finding out nicknames, what the students do at home, whether or not they like sports, who likes to debate. Watch Mr. Law and his students in his sixth-grade mathematics classroom and see how he builds relationships with his students.

Wilkie has been at Stehlik Intermediate School in Aldine ISD for 7 years and worked his way up the ranks. He began as a paraprofessional at the Nimitz 9th grade center, and his principal at the time encouraged him to get his teacher’s certification because Wilkie had such a good rapport with the students. He then got certified in special education and worked as an inclusion teacher for over a year, after which he was offered to teach in his own classroom as a full-time mathematics teacher. Wilkie jumped at the opportunity, and a couple years later, he also became the G/T teacher.

Mr. Law attended the RUSMP Summer Campus Program (SCP) during the summers of 2013 and 2014. When I asked him about the impact that RUSMP had on his teaching, he responded, “I know without a shadow of a doubt it has made me a better teacher. The stats speak for themselves.  When I look at my students’ performance, I see that I’m a much more effective teacher.”  Listen to Wilkie discuss the impact of RUSMP and the “thread” he was given at RUSMP that tied everything together so that now he feels like he can be a leader on his campus.

When you talk to Wilkie Law, it is apparent that he is a natural leader, and that both students and adults are drawn to and inspired by him. One of the things he likes to chant at school is “TGIM” (Thank God It’s Monday!) instead of “TGIF.”  After the first year of attending the RUSMP SCP, he was asked to be the sixth-grade team leader.  Recently, he was asked to present sessions at the new teacher induction for his district.  Listen to Mr. Law as he reflects about his new leadership roles.

Mr. Law’s decision to teach sixth grade was based on his personal experiences when he was in school. Listen to him share his poignant story about why he dropped out of school during sixth grade, and then came back to succeed during his second year of 6th grade, and how that experience shaped the type of teacher he is today.

After visiting his classroom, one phrase in my mind is “TGIW!” Thank goodness it’s Wilkie! Thank you, Wilkie for sharing your knowledge, enthusiasm, and understanding with not only your students, but also your colleagues.

How much money will you save buying a more fuel-efficient car? Use Algebra!

September 2nd, 2014 by Alice Fisher

How much money will I save buying a more fuel-efficient car? This seems like a common question when in the midst of purchasing a car, yet this question is more interesting mathematically than meets the eye.

A few weeks ago, my husband John and I were debating between buying a Honda Pilot and a Honda CR-V.  John was pulling for the more powerful Pilot (on the left) while I was leaning towards the smaller CR-V (on the right).

While I was test driving the CR-V, my husband asked the car salesman  how the gas mileages of the two cars  compared . We were informed that the CR-V’s gas mileage is 22 miles per gallon (mpg) for city driving and 30 mpg for highway driving; the Pilot is 17 city and 24 highway. Then we proceeded to figure out how much money would we save if we bought a CR-V.  Since we were buying a car for me and I drive about 75% of my miles on city roads, we estimated that the average gas mileage for a CR-V is about 24 mpg and Pilot is about 19 mpg.  An explanation on how to precisely compute the average gas mileage given the city and highway mileage and percent of miles driven on each type is given here.

At this point, things got interesting. I was test-driving an unfamiliar car so that my math wheels were not spinning properly during this mathematical conversation.   In the meanwhile, both John and the car salesman insisted that since the CR-V’s gas mileage is 5 less than the Pilot’s gas mileage, that 5 mpg difference, in addition to the  number of miles driven in a year and cost of gasoline are the only numbers needed to calculate the difference in annual gas costs between the two cars.

This conclusion didn’t feel right to me, but I didn’t have the mathematical justification at hand since my hands were busy steering a car that did not belong to me.  So once I had a paper and pencil in hand, I started working out the problem.  If you have a minute, I invite you to work it out as well.

Suppose we drive 12,000 miles per year and car A uses x miles per gallon and car B uses (x+5) miles per gallon. Then car A uses [12,000/x] gallons per year while car B uses [12,000/(x+5)] gallons per year.  Thus, the annual cost of gas for car A, y, is calculated as y = [($/gallon)*(12,000/x) gallons] dollars while  the annual gas cost for car B, z,  is z = {($/gallon)*[12,000/(x+5)] gallons} dollars.  When you simplify difference in costs, (y-z), in terms of x, the result is ($/gallon)*12000*5/(x^2+5x) or:

[($/gallon)(number of miles driven in a year)(5)]/(x^2+ 5x) dollars.

Examining this algebraic expression, we see that the difference in costs not only depends on the difference in gas mileages, but also on the gas mileages of the 2 cars.  The higher the gas mileage of the 2 cars, the less the savings are between the 2 cars, even if the difference in gas mileage remains 5!

Driving a CR-V instead of a Pilot would save us about $500 this year assuming that I drive 12,000 miles this year.  However, if we had been  choosing between a Toyota Prius (about 49 mpg) and a Honda Civic Hybrid (about 44 mpg), we would have saved only about $100 per year with the same parameters even though the difference in gas mileage is about 5 mpg.

You can calculate the savings per year at the following website: http://www.fueleconomy.gov/feg/findacar.shtml  However, you don’t truly appreciate the mathematical relationship until you’ve worked out the algebraic expressions.

Conclusion: My husband and I ended up buying the CR-V because as our car salesman wisely reminded us, “Happy wife, happy life.”


Coming next: Creating a program that will calculate the gas savings choosing a more fuel-efficient car.