Strip Generator Creates a black and white comic strip. Like other generators, all you need to do is select images from their library and drag and drop. You can save the comic online, print or embed into your own blog. http://stripgenerator.com/ **
Learn English Kids http://learnenglishkids.britishcouncil.org/en/make-your-own/comic-strip-maker from the British Council.
Make Beliefs http://www.makebeliefscomix.com/ ** Teacher Section available.
Witty comics http://www.wittycomics.com/ **
Piki Kids http://www.pikikids.com/ Allows you to create comics and t-shirts.
Chogger http://chogger.com/ **
Kerpoof movie creation studio ttp://www.kerpoof.com/ Teachers can manage student accounts and lesson plans available.
Creaza http://www.creazaeducation.com/You can create cartoons or personal digital stories.
Comiker http://www.comiker.com/ Create comics to share with online community; therefore not filtered.
http://www.mainada.net/comicssketch
Always review to ensure that one of these online tools is what you wish to introduce to students.
The list with ** are also featured on Mario Addesa's blog.