Date: May 2, 2008 11:31 PM
Author: Kirby Urner
Subject: Free geometry tools...

For those of you lucky enough to have one flatscreen
and keyboard per child, this might be especially
interesting, but also if you share computers and/or
just project:

Python + VPython, both free and open source projects,
from and respectively, will let
your students deliver moving pictures to the screen
based on very few instructions involving the concepts
we're supposed to be teaching (e.g. sine, cosine,
radians, degrees), and in a concise computer language
with job market value, so easy to prove relevance (as
in "what will we use this for??").

Example: the code below is sufficient to produce a
lissajous curve, with just a few lines omitted (click
plaintext view in web archive interface to see original

def lissa(): # you could make a, b arguments if you want
Lissajous curves:

Other ideas of a, b

a = 3.0
b = math.pi/2

for t in range(360 * 4): # 0-360 degrees * cycles
x = math.sin(math.radians(t))
y = math.sin(a * math.radians(t) + b)
ball = sphere(pos=(x, y, 0), radius=0.1,
color =


That might look intimidating at first, and it is,
somewhat, so if you're looking for topics for in-service
training, the gov wants you to have more of it anyways,
so why not enjoy the ride?

Python + VPython is a fun dynamic duo, will cost your
school nothing, except for the time and effort of
downloading and installing. Apprenticing students might
help with that, do in our flagships.

YouTube of VPython:

Re: 2D plotting capabilities: