To help teachers in urban schools implement technology in their science instruction, two science educators analyzed a number of models for technology training. This paper explores answers to the question of how to design technology sessions so that they are highly valuable professional development experiences for teachers. The models for these training opportunities include sessions for single-skill-level groups, heterogeneous groups, and individual conferencing. The major advantages of each model are presented along with explanations of the difficulties encountered. The analysis of these different models, and the discussion of the process through which the technology sessions were developed and refined, demonstrate ways in which other science educators can support the efforts of science teachers to use computer technology with their students. (Contains 14 references, 2 technology surveys, and a World Wide Web manual.) (Author/DDR)