Other data sources included copies of participants' daily lesson plans for the winter 12-week
internship, as well as classroom videotapes and supervisors' weekly clinical observation notes.
Each participant's portfolio, a requirement for the completion of the MAT program, was also
used as a data source. Portfolios consisted of two full units (12 to 16 days each) of instruction,
including rationales, goals, objectives, lesson plans, assessment instruments, and videotapes of
classroom instruction. These data sources were analyzed to document whether the preservice
teachers planned to teach or taught the nature of science explicitly.