Greetings,
PIXLR is a very capable free, web based paint/draw program.
If Abode were to put a version of the draw program, “Illustrator” on the web, the way it did with Photoshop, I suspect it would look very much like PIXLR.
This is a very full featured program with the basics plus an amazing number of extra features such as, layers, filters and amazing number of colour adjustment options plus tools like, “blur”, “sharpen”, a “dodge” tool, a “burn” tool and much more.
Even the interface, the menus, the general look and fee is very evocative of an Adobe product.
In addition, PIXLR also allows for images to be uploaded from and saved to the local desktop as well as imported from photo repositories such as Flickr and Photobucket.
Best of all, no account is needed to access and use PIXLR
Check it out at:
Enjoy 
Ciao, teachers!
Am Norwegian, but 2 days ago I released 30 video tutorials in basic use of photo editing program PIXLR in English.
http://www.ictpublish.com/pixlr
Happy new year
Haldor
Please check this out.
Haldor has created 32 screencasts on using the various PIXLR tools such as changing the size and shape of an image, adjusting colour and brightness, using the marquee tool, the smudge tool, etc.
The videos are free to watch and very well done.
Outstanding Haldor! Thank you.