The great thing about taking lessons outdoors is that you can learn about sustainability and the natural world by direct interaction with the environment.
I feel it is so important that schools should be models of sustainability and the best way for students to understand the issues involved, and also care about their environment, is to have hands-on experiences of it. We are very lucky to have a Victorian walled garden in our grounds, but there was a lot of hard but rewarding work involved before we could use it properly. Students, parents and teachers volunteered to work on Saturdays and the result has been a school farm with pigs that we raise and send to be slaughtered before being made into sausages by the students.
Students enjoy the hands-on aspect of their GCSE in Environmental and Land Based Science with 50% of their work being practical and 50% being theory. They say they find it easier to learn in this way. Initially there were some negative thoughts about the animals going to slaughter but they have generally been very accepting about this and have a much more thorough understanding of the process of food production.