Make a group object in which the pivot point is the at the center of the cube, put the cubes in there, place some text on top of the cube face, place that text inside that group object, and when you rotate the group, the cube and the text will rotate together from that center point of the cube. If text feels like it is not attached to the surface, adjust the Z so it is only a unit or 2 in front of the cube face. You can rotate the group 90 degrees, make a new text object outside of the group, line it up similarly and then place it as is in the group, so forth and so on until you have text 'on' every face of the cube you wish.
You can just make the text a child of the cube, but a group object is in my opinion a cleaner way to handle this, and gives you better animation control over visibility and whatnot.
#XPression