In our research on teacher adoption of instructional technology over the past decade—including work with several Preparing Tomorrow's Teachers to Use Technology, National Science Foundation, and Challenge grants—we've found two fundamental limitations to traditional adoption models and several strategies that facilitate sustainable change.

The traditional models of adoption are limited in two aspects that we've found to be critical to understanding how educational systems adopt technology and develop teacher capacity:

• An educational system is not a single social system; it is a decentralized organization with embedded subsystems of teachers within classrooms, schools, and districts.

• Traditional adoption models deal with internal organizational factors but tend to ignore external factors, such as the rapid worldwide evolution of the internet, shifts in national priorities for funding educational initiatives, and the presence of change facilitators within a networked educational community.

Because a school or district is a plurality of embedded, interacting, and essentially autonomous people and groups, we can draw from the growing research on complex systems to better understand how change is sustained. And because schools and districts are themselves embedded in a larger social and political reality, we know that some of the facilitators and barriers to change are out of the control of the organization. These two facts provide us with a new perspective on "adoption" and "sustainability" of change in educational technology.

Encouraging adoption of instructional technology

Adoption of technology in educational systems appears to follow a stage model. Teachers seem to progress through five stages at which they gain comfort, confidence, and competence with instructional technology—sometimes sequentially, sometime skipping steps. At each stage, certain critical features must be present within the educational system.

• Stage 1 (Teacher as Learner): Time for participating in training and ongoing professional development by peers, and in-service sessions that stress best practices in aligning technology with curriculum and standards;

• Stage 2 (Teacher as Adopter): Online resources, open-lab workshops at school sites to solve specific technical problems, readily accessible technical support, and technologically-savvy peers;

• Stage 3 (Teacher as Co-Learner): Collegial sharing of ideas for integrating technology with standards-based instruction, exemplary products and assessment ideas, and use of students as informal technical assistants;

• Stage 4 (Teacher as Reaffirmer): Administrative support, a valued incentive system, awareness of intermediate outcomes such as greater student engagement and increased metacognitive skills, and evidence of impact on student products and performances;