+ A Lesson in Green...

With more and more issues of energy usage and conservation coming to surface within the past several years, one challenge has always been educating the general population and helping influence them to make better decisions about their energy consumption. However, what if the advantages to being a little greener were introduced to children as young as second grade? Elementary students around the world work through math story problems asking how many apples Suzie would have left if she started with nine and gave Johnny five, but what if these problems could be focused to cover a lesson in green as well as mathematics? Below are a few possible examples of some story problems for you to try if you dare ask one question: Are you smarter than a green 5th grader?


Today's Quiz -

1) Jodie’s mom recently read that it takes energy equal to 0.42 gallons of gasoline to produce and ship a single pound of beef, and energy equal to 0.01 gallons of gasoline to produce a single pound of vegetables. If her family consumes 25 pounds of beef and 35 pounds of vegetables every month:

a) How much gasoline does it take to produce the beef they eat?
b) How much gasoline does it take to produce the vegetables?
c) How many times as much gasoline does it take to produce a pound of beef compared to a pound of vegetables?



2) Mike just bought a new handheld game system with his saved allowance. He is trying to decide whether to buy rechargeable batteries or disposable alkaline batteries. Over the course of the year he will need either 48 disposable batteries which cost 85 cents per battery or 8 rechargeable lithium batteries which cost 2 dollars each.

a) How much will it cost Mike for a year of disposable batteries?
b) How much will it cost Mike for a year of rechargeable batteries
assuming he already has a charger?



3) Joanne lives in Cincinnati and wants to visit her sister in Chicago for the weekend. She knows that using as little gasoline as possible helps the environment and she can either choose to take a Megabus or her own car. The trip is 320 miles. Her car gets 30 miles per gallon and she’ll be the only person in it. The bus gets 10 miles per gallon on the highway, and 35 people typically ride on this bus at the same time.

a) How much gasoline will Joanne’s car need per person to make the trip?
b) How much diesel fuel will the Megabus need per person?
c) (Extra credit) If burning a gallon of gasoline creates 20 pounds of carbon dioxide ("CO2"), and burning a gallon of Diesel fuel creates 22 pounds of CO2, how much less CO2 will Joanne's trip take if she takes the bus instead of the her car?



How do you think you did? Below you can find the answers to the above problems in order to check your work. Ok, so maybe you found those math skills are a little rusty. Regardless, teaching elementary school children about the benefits of being green, as proposed by energy consultants and agencies such as NASA, should be a positive step.


Solutions:
Solution #1:
a) 25*.42 =10.5 gallons of gasoline
b) 35*.01 = .35 gallons of gasoline
c) 1 pound of beef requires .42 / .01 = 42 times as much gasoline compared to a pound of vegetables.

Solution #2:
a) 48 * $0.85 = $40.80
b) 8 * $2 = $16

Solution #3:
a) 320miles/ (30 miles per gallon * 1 person) = about 10.7 gallons of gasoline per person
b) 320 miles / (10 miles per gallon * 35 people) = about .9 gallons of diesel per person.
c) The car trip would generate 10.7 gallons * 20 lbs per gallon = 214 pounds of CO2. Joanne's share of the bus trip would generate .9 gallons * 22 lbs per gallon = 20 lbs of CO2. Taking the bus will save 214-20 = 194 lbs. of CO2!