Background/Question/Methods As an extension of the NSF GK-12 program at the University of Pennsylvania, we have been working with high school biology teachers from the School District of Philadelphia for three years through monthly professional development sessions.  At each session, now funded by the School District of Philadelphia, we present teachers with activities designed to integrate inquiry and content, supplies to perform all activities, and advanced biology background information.  As part of an ongoing study, teachers who attended any of the first three professional development sessions in the 2007-8 school year were given a modified version of a published science process skills assessment to administer to their students.   This assessment was used to establish a baseline for students’ ability to develop hypotheses, analyze data from graphs and tables and operationally define variables with the goal of improving professional development sessions through a more targeted approach.  Twenty-one questions were grouped into four main categories: variables, hypotheses, and data interpretation from graphs and from tables. An additional category, data-hypothesis, addressed students’ abilities to distinguish between a correct restatement of data and a valid hypothesis as the reason for data presented in a graph.  We predicted from our past experience with Philadelphia students and teachers that students would perform better on the questions in the hypothesis and data interpretation from tables categories.
Results/Conclusions Of 35 teachers who were given the assessments, 15 returned them, yielding assessments from 1006 students. The teachers come from a wide variety of public school types ranging from non-selective neighborhood schools with enrollments of several thousand to selective charter schools with enrollments of a few hundred students.  On average, students answered 10.9 ± 0.1 out of 21 questions correctly.  This ratio of correct to incorrect answers was consistent across all five categories; students did not perform better on any one area of the assessment.  We did find that students at schools that require an application to attend, whether or not the school was selective, answered 2.9 more questions correctly than students who attend their neighborhood school (12.6 ± 0.2 compared to 9.7 ± 0.2).  We have used these data to inform the lessons we provide during the professional development sessions which now address all science process skills from the assessment.  At the end of the 2007-8 school year we will present the teachers with a follow up assessment to evaluate students’ growth  and help us plan future professional development sessions.