Publications by John E. Opfer

Nehm, R. H., Beggrow, E. B., Opfer, J. E., & Ha, M. (2012). Reasoning About Natural Selection: Diagnosing Contextual Competency Using the ACORNS Instrument. American Biology Teacher, 74, 92-98. Retrieved from http://www.jstor.org/stable/10.1525/abt.2012.74.2.6 (Original work published 02/2012AD)
Federer, M. R., Nehm, R. H., Opfer, J. E., & Pearl, D. (2014). Using a Constructed-Response Instrument to Explore the Effects of Item Position and Item Features on the Assessment of Students Written Scientific Explanations. Research In Science Education. http://doi.org/10.1007/s11165-014-9435-9 (Original work published October-29-2014)