You can download a free FTP client from Fetch for MAC by providing some student information. Go to http://fetchsoftworks.com/fetch/free
After you download and install the software start it by clicking on the icon that looks like a dog.
When it opens it should look something like the picture below:
Click on Fetch and then select Fetch Preferences as shown above.
Uncheck "Use passive mode transfers (PASV) as shown above and complete the new connection settings as below.