All the hex's lit up.

[Civ5 Fanantic]

HELP!. All of a sudden every hex in the game showed it's worth, how do I turn it off, please and thank you.

 

[Browd]

Sounds like you inadvertently turned on display of hex yields. Next to the minimap there are some icons to pull up some map display options. Just deselect show tile yields. You can also try ctrl+y as the shortcut hotkey combo to toggle the display of tile yields.