Grant Snider and his brilliant math comics
A picture speaks louder than a thousand words, and my friend Grant shows this is very true indeed:
Acknowledgement: The creations you see here belong to the genius known as Grant Snider, who has kindly allowed me to reproduce them on this page. Do support his blog Incidental Comics.
[ His exact response to me over the internet:
Thanks for the email. Feel free to repost any math comics from my site, with proper attribution (include my name and link back to my blog). Best of luck in your teaching!" ]