The latest and best are the high-definition backlit jobs where you can use the board without standing in your own light and blocking out the very image with which you are trying to interact. Needless to say these are a bit pricey, and the bulk of the boards being bought for and by schools are the standard form that uses an ordinary data projector. It is these devices that are being hailed as finally supporting the ICT that is revitalising classroom teaching, grabbing children's attention and keeping them rapt as teachers show off their newly acquired multimedia talents.
Clearly the opportunity to share a screen image with the whole class is enormously valuable. Whether this is in order to view teacher-prepared resources or pupil work, being able to show resources to everyone at the same time, and manage an activity or series of activities around those shared resources, it is indeed potentially transforming. After all, it is no coincidence that some form of shared-viewing technology has been part of a classroom since time immemorial. The interactive whiteboard moves this shared space into the 21st century, offering all the communicative potential of fully interactive multimedia. Moreover, with an interactive whiteboard you can manipulate what you see in the most natural manner imaginable - by touching it and moving things around.
There is a question mark though as to how much the learners actually get to use this feature themselves, or how important this feature is for all but the youngest, or in contexts where that direct sensory link remains important. It seems that teachers adopting interactive whiteboards are inclined to use them to support whole-class teaching that is both teacher-led and teacher-focused. Children, encouraged by the supporting visuals, will listen for longer, and so teachers talk for longer, leaving less time for pupil activity. Does this matter? An inspiring teacher can convey much that is valuable to pupils by leading class discussion and managing a whole class of students who are engaged and working together.
But where does this leave the "personalised learning" agenda? And to what extent can teacher-led activity foster the autonomy essential to an individual who needs to become and remain an active learner for the rest of their lives? If all the focus and the excitement is at the front of the room, is that not where the responsibility for learning will be seen to lie?
Perhaps this effect will be short lived. As teachers become used to the technology and pupils less impressed by it, it may fade into the background. Certainly some teachers began very early on to use the boards for group work, with the pupils using the technology themselves to support a shared activity. At which point, they may wonder why they have a fixed, rather small and expensive projection surface permanently fixed to the wall and dominating the classroom.
My fear, however, is that the heady experience of holding 30 children rapt with an interactive whiteboard will make it even harder for everyone to move the focus of learning to the individual rather than the class.
Angela McFarlane is professor of education and director of learning technology at the Graduate School of Education at the University of Bristol