Text editors

If you are intrepid you might check out the discussion here:
http://moodle.org/mod/forum/discuss.php?d=96160&parent=425714

But, and though it would be great to have someone testing the work Mauno and others are doing.....

Having worked in a high school computer lab I frankly have to agree with Steve's suggestion... if this is a public school situation and you have the authority, install Firefox, set up autoconfiguration and proxy and think about using one of the kiosk apps. Firefox is not coupled to the OS, you can manage access just fine (especially if you have squid installed), it is not subject to Safari's past limitations. Your only issue may be autoupdate, but you can easily disable that if you want.