Valparaíso is a gem.

I loved my study abroad experience with CIEE. Some important things to know are that a majority of students are placed in families in Viña del Mar as opposed to Valparaíso (kind of the more upscale, suburbany sister to Valpo. It may be safer but has less character). Valparaíso is a great place to be a young person. There are numerous students around due to the multiple universities, and it's a great place to go out - whether you like clubbing or just finding smaller spots with music and wine. Valparaíso is one of the most beautiful cities I've ever been as a result of the architecture, artwork/graffiti, hills, and the ocean. Public transportation is great. The social/political history is fascinating.

CIEE was very supportive. They helped me find a non-profit to volunteer with. The Chilean students who work for them had a major impact on my stay, inviting me into their friend groups, helping me choose classes, practice Spanish etc. All of my classes at PUCV were lecture based except for my Spanish and Chilean culture class (which was great). There's not a lot of accountability for foreign students in the university system in my experience, which was great because it gave us freedom to travel (where I learned the most).