Simplify the following text for a Grade 2 native English-speaking person.
Original: North to south highways are odd-numbered , with lowest numbers in the east and highest numbers in the west .
Simplified: For east\/west U.S. Highways , the small numbers are in the north and the big numbers are in the south . For north\/south U.S. Highways , the small numbers are in the east and the big numbers are in the west .