Right now I'm practising Yoga at the University of Warsaw. It is all right, however, I think I can find something more sophisticated. Furthermore 70 PLN a month is very expensive for a university course.
Can you recommend any school in Warsaw?
You didn't precise whether you have any particular preferences connected with location, I can recommend one place in Praga district, take a look at their site: jogapraga.pl
Sorry, I forgot to emphasise that I prefer a place on the western side. Hence, somewhere closer to the city centre.
Bielany and Mokotow would also be appreciated.
I subscribed now to jogafoksal.pl until the end of the month to test them. They offer a lot of different times so almost everybody can find his desired time frames. Furthermore they have two schools in ul. Dluga and ul. Foksal which are very central located. Students pay 30 PLN weekly.
The only downside, however, is that the practices are very therapeutic and slow (if I recall it correctly it's the Iyengar style). I'd prefer a bit faster joga style though.