Speak with your instructor before class. Using binoculars could be distracting to students around you and the instructor should be informed ahead of time about why you need the binoculars and how you plan to use them.
Sit in the back of the room or hall to limit the distraction you'll provide to other students.
Adjust the binocular lenses before class so you'll be able to see all notes and actions clearly.
Lift the binoculars to your eyes whenever new notes are written on the board or screen so you can accurately read them. Then put the binoculars down so you can take notes. Also use the binoculars during a lab or demonstration in which you need to see the steps or process clearly.