This paper presents a case study of a technology professional development initiative and illustrates how a workshop approach based on technology, pedagogy, and content knowledge (TPACK) was adapted for professional learning at a school site. The case further documents how three middle school science teacher participants developed knowledge about how to teach with technology as they planned and implemented a blog activity in science over a 4-week period. The design of the professional development was informed by the underlying assumptions of the TPACK framework and characteristics for effective professional development for science and technology-enhanced teaching. To obtain insights into the particular experiences of teachers as they participated in the onsite professional development, a naturalistic case study design was used. Data collection procedures included researcher field notes during workshop sessions and lessons, videotaped classroom observations, audiotaped interviews, and teacher and student lesson artifacts. Data on teachers' planning and lesson implementation of the blog activity to Grade 8 students were analyzed using content analysis. Overall, the results indicate that TPACK is developed through a combination of workshop experiences and immediate application of knowledge gained in the workshop into practice in the real-life teaching context.