side bar menu and category page

This is about http://www.beaconacademy.org/dev-wpbeacon/wordpress.

Here is my problem:
About Beacon – Faculty – uses a bio plug in that has a really easy interface. The problem is I cannot get the left sidebar menu to work. How is that set. I added a custom menu and it didn’t work. Is my stylesheet overwriting something? I am technical so your answers can be technical. I am new to WordPress.

THANKS in advance. Linda