# Sidewalk math!

With awesome weather all around, we just had to work on math outside, in chalk, on sidewalks around campus!

From Mrs. Baldwin:

The Trig/Prob/Stats class learned about describing data with numerical summaries and graphical displays. We took our work outside to practice these skills. We studied a data set of travel times to work for 20 NYC residents. We found that the median travel time was 22.5 minutes, the minimum was 5 minutes and the maximum was 85 minutes. Students also learned to use a new measure of spread called the interquartile range. This measures the range of the middle half of observations. We found that the middle half of travel times for these New Yorkers vary from 15 minutes to 42.5 minutes. Working outside in the chalk brought a kinesthetic element to our learning that was fun and engaging.

From Mr. Seamon:

# Calculus in Ancient Babylon!

This just in from Mrs. Hill!

It has long been a subject of debate among mathematics historians whether Isaac Newton or Gottfried Leibniz first invented calculus. It turns out that they both may have been beaten to the idea by the ancient Babylonians as far back as 350 BCE. In a recent Science article published on January 28th, we learn that new evidence suggests that the Babylonians came up with techniques for measuring the paths of planets, the sun, and the moon across the night sky that involved the fundamental calculus idea of Riemann sums.

Between 2002 and 2008 astroarcheologist Matthieu Ossendrijver of Humboldt University in Germany noticed drawings of trapezoids in various tablets held by the British Museum. Then in 2014, Assyriologist Hermann Hunger of the University of Vienna visited Ossendrijver, bringing pictures of another Babylonian tablet with computations identical to those from the British Museum tablets. Ossendrijver realized that the Babylonians were using trapezoids to approximate the distance traveled by Jupiter across the sky from their velocity curves. This is a discovery central to the idea of integral calculus.

At Williston Northampton School, our calculus students still use similar techniques to develop the concept of the integral. The photo below shows a poster created last year by Maddy Stern ’15 in Martha McCullagh’s calculus class that highlights this same idea. Little did she know that the Babylonians had been doing the same thing over two-thousand years ago!

# Two new student screencast playlists

I just finished putting two new student screencast playlists online from my BC & Multivariable Calculus class. Enjoy!

Here’s a particularly strong student video from 13.3:

# Algebra 2 and Multivariables Calculus Student Videos

Want to learn some Algebra 2 and/or Multivariable Calculus? Learn ’em from my students!

# Hyperbolic Paraboloids

One of my favorite surfaces is the hyperbolic paraboloid. So, of course, all of my students need to know how to fold one from a square sheet of paper. Last night my BC & Multi students practiced their folding skills and today in class their quiz was to fold one on their own without the instructions. They certainly impressed me with their folding skills!

Here are the instruction (PDF). Try folding one!

Their homework creations:

Folding quiz:

The hyperbolic paraboloid lineup!

A family:

The hallway bulletin board:

# Math Posters

Check out the amazing math posters currently on display on the second floor hallway of the Schoolhouse: