What I enjoyed most about my co-op experience was that I was able to improve my communication skills along with my programming/development skills. I mostly had to work with my team to develop a product using my Java knowledge in an agile environment.
At rare times there seemed to be endless work, where I stayed in the office decently late to finish up my tasks. But for the more frequent times I wouldn't have as much responsibilities and even when I would ask my boss if there was more work, they wouldn't really have anything for me to do. Overall I would be bored some of the times.
Being laid back is great, but the co-ops need to learn more about handling responsibilities and dealing up front with problems.
My Office for most of the time was quiet, but not extremely quiet, meaning there would be people chatting here and there. But sometimes people would group together around one computer to solve a problem and have a discussion about whatever topic, which would be entertaining and fun.
Don't be afraid to ask as many questions as you want to whomever. You're hear to learn.