Study / Learning Polish in Poland - best schools? [4]

Hello, I'm a UK student who has just finished college and have offers to study at university this following year but i'm having doubts about my current subject choice. To get to the point I'm of polish heritage (grandparents on both sides of the family are from poland) and my polish is very poor. I have family all over Poland but the two major cities which come to mind are Szczecin and Katowice. Does anybody know of any good language schools in these two cities? I'm looking for something like a 6 or 12 month course.

Thank you all and sorry for troubling you.