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2. Alberta Learning. (2004). Focus on Inquiry: A Teacher’s Guide to İmplement Inquiry-Based Learning. Learning Resources Centre.
3. American Institutes for Research. (2005). Effects of Outdoor Education Programs for Children in California. American Institutes for Research.
4. Athey, C. (2007). Extending Thought in Young Children: A Parent–Teacher Partnership (2nd ed.). Sage.
5. Back to Nature Network. (2012). Into Nature: A Guide to Teaching in Nearby Nature. Back to Nature Network.