1. Baker, M. (2013, August). Theory, research, and rationale behind the Focus on K2 curriculum. Boston Public Schools Department of Early Childhood. Retrieved from http://bpsearlychildhood.weebly.com/uploads/1/0/1/3/10131776/focus_on_k2_literature_review_final.pdf .
2. Barnett, W. S., Carolan, M. E., Squires, J. H., & Clarke Brown, K. (2013). The state of preschool 2013: State preschool yearbook. New Brunswick, NJ: National Institute for Early Education Research.
3. Boston Public Schools Department of Early Childhood (2014). Introducing Focus on K2. Retrieved from: http://bpsearlychildhood.weebly.com/introduction.html .
4. Boston Public Schools (2015). Boston Public Schools at a glance. Retrieved from http://www.bostonpublicschools.org/cms/lib07/MA01906464/Centricity/Domain/4/BPS%20at%20a%20Glance%2015-1109.pdf .
5. Bronfenbrenner, U. (1979). The ecology of human development: Experiments in nature and design. Cambridge, MA: Harvard University Press.