Expectation seems to be the most influential part of analyzing one's experience. It is hard to sum up an entire 5 months in a paragraph, and my personal experience cannot equate any other volunteers- but that may be the most important thing to know going in to EOD. You need to know what you expect to contribute and to recieve from the program and be flexible and willing to take it for what it is. The program is not 100% professional and expectations are not very high for volunteers; however, that is just what I was looking for. I got experience teaching in a informal way, and I got to live in another country in a very relaxed and fun way with little work demands or expenses. Also, the Chilean Ministry of Education may seem a little unorganized, and the students may be more rowdy than in the United States- but that made it less stressful for me.
The teaching is what you make it. If you have teaching experience and you put in the time to make great lesson plans- it can be really rewarding. If this is the first thing like this you have ever done, then that is fine too because there are no expectations for you- they are happy to have a native speaker. It depends on how commited you are to teaching, or if teaching is just secondary to you exporing another country. Also, you experience will depend greatly on your relationship with your co-teacher.
Chile is an amazing country. Your experience will be totally different, depending on what city/region you get placed in, but the people are beyond inviting. I have made friends for life. Also, the travelling is cheap and easy, and there are innumerous places to explore! I went somewhere EVERY weekend and enjoyed every minute of it. Also (if you try) you will be able to be conversationally fluent within months! The improvement in Spanish alone is invaluable.
It is a great experience and I learned so much from many aspects. It is a safe, beautiful country with great relationships and incredible travel opportunities. I felt totally comfortable there 100% of the time. I would recommend this experience if you are flexible and laid back. If you want everything to turn out just as it is written, you might not want to work for the Chilean government.