Permissions problems

[Captain Ahoy]

Hello there. I am very new to scripting in terminal. We no longer have a mac tech at our college and I have a permissions problem where I have a lab of dual 2.3 G5's running leopard 10.5.8 and they have two hard drives. How we have set it up is that on one drive (called "System") we have all of the applications. We only allow read access to this drive for all our students. However on the second drive (called "media") I want all files and folders to be read/write for all users, groups, and everybody. I have gone into system info on the media drive ("cmd i") and clicked on "ignore ownership on this volume" and then clicked "apply to enclosed items". This changes the "read only" to "read and write" for all folders, subfolders and files on the "media" drive that already live there. However, any new folders retain the old permissions set up (ie user "read and write", group "read only", everybody "read only". I have read online that you can use the sudo chown -R command, but I seem to be doing something wrong. I keep getting "command not found". I have been banging my head against the wall for some time now trying to figure this out; so I thought that I would post a thread to see if anyone had any ideas as to where I should go from here. Thank you in advance for any help that anyone gives me.