Archive for January, 2011

Delaware School Achieves Success With Singapore Math Adoption

Friday, January 28th, 2011


An article published by the Rodel Foundation of Delaware describes how Kuumba Academy took a serious approach to remediating the problem of poor math achievement. They adopted a Singapore Math curriculum, and with it, they gave their teachers “intensive, on-going professional development to deepen teachers’ understanding of math instruction at the elementary level.” The school also implemented parent workshops and a “Bring Your Parent to School Day,” which would help parents and guardians understand the sometimes very different approaches Singapore Math takes.

One minor incorrect point the article states is that Singapore Math uses math sprints to strengthen math skills. Sprints were developed by Yoram Sagher, a US professor, to supplement math fact practice in the Singapore Math curriculum. Using them can help, although they are not the only effective math skills practice approach.

Adopting the Singapore Math curriculum, along with training teachers well and using sprints, led to a complete turnaround in the school’s math test results. As the article states:

Since Kuumba began its partnership with the Vision Network, the school has seen phenomenal growth in math scores. Not only are students no longer falling behind, they are exceeding state performance in many grades in math. In just 3 years, Kuumba went from 49% of students meeting the standard school-wide to 87% proficient, as measured by the DSTP.

Math Joke Animation

Friday, January 7th, 2011


It snowed today – a lot – canceling all my plans and making it a perfect day to get things done at home. So I created the short movie below. I hope you enjoy it as much as I enjoyed making it! This one was taken – and highly modified – from a joke told in Math Jokes 4 Mathy Folks.

Lateral surface area of a cylinder

Sunday, January 2nd, 2011


How do you explain the concept behind the formula for the lateral surface area of a cylinder, which is 2Πrh? I ran into this question when tutoring a student to prepare for the New York State Integrated Algebra Regents exam. (For some reason, this exam contains a lot of geometry.) The lateral surface area is the area of the cylinder’s surface that does not include the circular ends.


If you look at the cylinder, it resembles a can. If you imagine it is a can of something, the lateral surface area is what the label covers.

So to show the concept behind the formula, we took a can of organic garbanzo beans out of the kitchen cabinet. Fortunately, it had a label that was easy to peel off.

First we measured the width of the label. Next we measured the diameter of the can (the 2r, or twice the radius), and multiplied it by Π. Comparing the two widths, the rectangular label width pretty much matched the formula for the circumference, or a little over three times the diameter exactly! And since the label is a rectangle, to get the area, we multiplied the length by the height.

So we discovered, by this exploration, that the width of the label is equal to the circumference of the circular top. Therefore the formula made sense to the student, and we had fun making it concrete. If she doesn’t remember the formula on the test, I’m sure she’ll be able to access the concept to recreate the formula at the point – and that will demonstrate true understanding.


Get every new post delivered to your Inbox

Join other followers: