Creating mathematical diagrams for free

To excellent options for creating mathematical diagrams are Google Drawings, and Diagram.ly. The chief advantages of Google Drawings is that you can save, edit, and collaborate (good for group projects) on your drawings later. The biggest advantage of Diagram.ly is that it doesn’t require sign-in (useful for working with students), and it has many more options for creating your diagrams.

Cylinder with 20cm diameter

Created with http://diagram.ly

Created with Google Drawings

Advertisements

Adding Geogebra files to your hosted WordPress.com blog for free

You can use a combination of services to allow users to access Geogebra files you’ve created for free through your WordPress blog.

  1. First, sign up for Dropbox and download the application to your computer (or access their service through their website).
  2. Next, download and install Geogebra.
  3. Create an example with Geogebra, and export it to html.
  4. Upload the exported .html file to your Dropbox account (either through the Desktop client or the Dropbox website).
  5. Find the public link to your .html file and copy it.
  6. Insert the link into your WordPress site and update/publish your post.

If you know a little bit of HTML, you can then update the exported .html file with the link back to your blog for a more seamless experience for your blog readers.

See this Geogebra applet (requires Java) of the upper and lower sums for a quadratic function as an example.


Post by phone to WordPress example

See these instructions on posting audio recordings to a WordPress blog from a phone. As I share below, this would potentially allow your students to post entries to your class blog from any phone.


Embedding videos

This is an example of embedding videos from third party sites. The videos below were created by teachers as part of a workshop.


Testing mathematical equations and graphs support

You can enter fractions and other mathematical symbols in a WordPress blog (see this page for an explanation of how to get started). I’ve taught students as young as grade 6 how to use simple LaTeX. Here’s an example of a fraction. \frac {4}{5}

You can write more complicated formulas and have them render in WordPress. Here are a couple of more complicated examples (thanks to John Forkosh for the LaTeX code). If you need to figure out what LaTeX code to use, check out this online equation editor from Code cogs.

\Large e^x=\lim_{n\to\infty} \left(1+\frac xn\right)^n

\large f^\prime(x)\ = \lim_{\Delta x\to0}\frac{f(x+\Delta x)-f(x)}{\Delta x}

You can use Google’s Chart Wizard to add graphs (many different kinds available) to your posts. See this graph for example:

Sample pie chart

Update: The image above is broken because of some weird secure https caching mechanism WordPress.com is using. This will work fine on a personal blog, or you can just save the Google Charts image to your desk and upload it to WordPress.com