I'm trying out the trial version to see if this software will work for our non-profit.  I'm totally new at this and have no programming experience.  

I've got a contact form that I'm happy with but for one thing.  I have a drop down field that has 3 school districts listed as choices.  The next field I want is School, but I want the School field to be populated with choices based on what was selected in the districts field.

How do I do that?

Thanks in advance for any help.