Hi Jill,
Are you labelling a regular grid of streets, or are they at angles in between 0° and 90°? Do you have a rotated dataframe? If your streets are mostly perpendicular, with an unrotated dataframe, straight labelling should work for you, but if some streets are at other angles, you will have to use a workaround. If you try and divide your features into two labels classes using SQL queries, you could set one label class to horizontal and the other could use Rotate by Attribute to add 90° to each label.
Sorry we don't have a better solution for you.