Teachers will have most evenings free as well as some time on the weekends. What you do with that time is up to you. If you choose to explore the city of Pohang, there are plenty of restaurants and shops that will pique your interest. The university offers free bus rides downtown where you can catch a movie, spend some time shopping, or visit the Dunkin' Donuts for a donut and a cup of joe.
On the weekends, you may care to travel out of town. Short trips include Busan and Gyeongju. Both sites are worth a visit, and they are unique experiences in Korea. Gyeongju is the capital city of ancient Korea where you can find many many Buddhist temples, burial mounds, and other sites of historical significance. Busan (or Pusan) is the second largest city in Korea and is a great place to find seafood markets, entertainment, and lots of shopping...anything from Korean souvenirs to vintage clothing. Another short trip is Andong to the north where you can find the historic Hahoe Folk Village, a picture of the ancient village life...a very worthy and informative venture.