Excitement about handhelds must be tempered by an understanding of what is typically required when any new technology is introduced into classrooms. We know, for example, that to succeed, handheld initiatives will need clear educational objectives and a logical theory of action that guides implementation. We can anticipate that teachers will need opportunities to learn how to use handheld computers if they are to integrate them successfully into instruction. Teachers will also need ongoing technical and pedagogical support to sustain changes they make to their instruction over time.