Assignment 2 asks you to turn in an ER or UML diagram. What tool should you use? Here are some of the options.
Those are tools that are designed primarily for making diagrams. Their main advantage is simplicity, since they are only helping you to make a diagram, not an actual database.
MS Access is installed in the Lab and has a UML toolbar
Dia is an open source program that does not provide all the features of Access but would be enough for this assignment.
On Windows: First install GTK+ for Windows, then install Dia.
On Linux: Exact installation would depend on your distribution, but
should be fairly straighforward in most cases. (E.g., on Ubuntu you
would need to run sudo apt-get install dia.)
On OSX: The website at http://dia.darwinports.com/ claims to have a Dia installer for OSX. I did not try installing it myself.
There are many UML editors out there. I do not recommend any, however, since most that I tried are much more complicated than you would need for this assignment. UML is a huge language, and those tools do nothing to hide the complexity from you. Additionally, such tools often want to generate actual class code based on your model, and since you are ultimately designing tables, not classes, it will only complicate things further.
Database design tools allow you to design a database model in such a
way that you can then generate database tables from it. While this
may be useful in some situations, this does make those tools a lot
less flexible than Dia or Visio. Since this assignment is primarily
about designing a document, rather than a physical database, you may
find the tool getting in your way. If you do want to try, however,
Ray recommends DBDesigner, which if free and can run on either Linux
or Windows.
You can download DBDesigner from http://fabforce.net/dbdesigner4/. The installation is pretty straighforward on Windows but may be a little painful on Linux. (See this thread for guidance.)