To play an example, click on the right-facing arrowhead in the example. To see the score in full-screen mode, click on the icon on the lower right of the example. It appears to be four tiny arrows pointing to the corners of an imaginary square. Once the full screen appears, click on the right-facing arrowhead.
Depending on your browser, you may hit Escape (Esc), Ctrl-[ or Cmd-[ to return from full screen.
Some score examples can be very detailed and difficult to read. Suggestion: Click on the image for the score and the image will open in your browser. You can then download the image, which can be viewed with Adobe Reader, Apple Preview or any other image viewing program. Use that to see and move around the score when you’re listening to the example.