Exploring Data is a website that I created in 1997 while working as the Raybould Fellow for Education Queensland.

It is a bit long in the tooth but the paper-based resources on the website are still useful. If you teach introductory statistics, it is worth a look around.
http://exploringdata.cqu.edu.au/index.htm

A clever web page for constructing a bar graph on the fly. All the necessary elements are editable - scales, axis labels, title, etc.
http://www.amblesideprimary.com/ambleweb/mentalmaths/grapher.html

This flash program shows the consistency of sample means from variously shaped populations. A student can change sample sizes, view raw data, choose samples singly or by the thousands, and observe changes as the sample numbers and populations change. It is also available as a stand-alone program (recommended for the classroom as it can be shown in full screen mode).

http://www.teacherlink.org/content/math/interactive/flash/sampling/sampl...

Line up the people in order of height. Then find the median, Q1 and Q3. For some reason they all look very cranky...
http://www.subtangent.com/maths/median-and-quartiles.php

A wonderful interactive version of this classical device.
http://www.subtangent.com/maths/ig-quincunx.php

The Stroop Test is a fun and engaging way to collect numerical data for later analysis and display. From the flipchart: "In the Stroop Test, the participants are given a list of words, and are asked to say the colour of the word, and not the word itself ... Most people take longer to say the colour of the word when the colour of the word doesn't match the word itself."

http://www.babynamewizard.com/namevoyager/lnv0105.html
The Baby Name Wizard is a fascinating website that graphically displays the number of babies with different names over the years. You can easily track the popularity of different names. What do you think was the most common boy's name and most common girl's name in 1990?

Note that the website takes some time to appear as it has to download a lot of data. Be patient!

The Baby Name Wizard is a fascinating website that graphically displays the number of babies with different names over the years. You can easily track the popularity of different names. What do you think was the most common boy's name and most common girl's name in 1990?

Note that the website takes some time to appear as it has to download a lot of data. Be patient!

http://www.peterrussell.com/Odds/WorldClock.php
The World Clock website has continuously updated information about the world such as the world population, number of births, number of deaths, number of cars and the number of barrels of oil produced. It is a wonderful discussion starter for a number of maths topics including time series data and rates of change (gradient).

The World Clock is a one page flipchart that links to a website:
http://www.peterrussell.com/Odds/WorldClock.php

It continously updates information such as world population, births, deaths, number of cars produced, number of barrels of oil produced. A wonderful discussion starter for a number of maht topics including time series data and rates of change (regression).