The Model Science Lab, a constructivist approach to teaching, strengthens urban science teachers' teaching practice. The retention rate of Houston science teachers who took part in the program was found to be very high and the cost of the Model Science Lab has proven less expensive per student than most other professional development options.

For many, the dominant model of curriculum development in science includes generating a topic, clarifying science content, identifying activities associated with the topic, and figuring out an assessment. Unfortunately, this approach tends to overemphasize activities and underemphasize mastery of science concepts and the process of scientific…