Every Monday from 19:00 -21:00 at Arkitektenes Hus, Josefines gate 34, Oslo. 70kr for non-students, 50kr for students. It's really good practice. I haven't done this for a while and it's a bit of a challenge to capture a pose in 1 minute, but as I said, really good practice and very enjoyable. The atmosphere is very relaxed and anyone and everyone are welcome. There is also a session every Wednesday at Einar Granum kunstfagskole, Maridalsveien 17, Oslo.