Why are my top-row keyboard buttons not working on Mac Lion? A kid tampered with System Preferences on my Mac Air running Lion, and now, none of the top-row keyboard buttons work. For instance, altering screen brightness, toggling the dashboard, and altering volume don't work.

There does seem to be some mismatch though. For instance, pressing the eject button now takes me to the dashboard.

How can I restore the default functionalities of the top-row keyboard buttons?
If you check the Keyboard pane in System Preferences, you should see an option called Use all F1, F2, etc. keys as standard function keys. I think you'll find it checked. The default is to have it unchecked.

Then within the Mission Control pane in System Preferences, I think you'll find that "Show Dashboard" is set to F13. The default is F12 (note that the default doesn't work if Use all F1, F2, etc. keys as standard function keys isn't checked).