The paper will describe research undertaken to investigate how children can be assisted to construct web based 3D worlds. As new technologies become an increasingly important part of children’s lives, we need to explore how such technologies can support children’s learning in ways that are stimulating and meaningful. Our previous research has investigated how children in primary schools can become producers as well as users of computer based systems, and have looked at their construction of multimedia and their use of internet connectivity. Building on this work, we have been investigating children’s use shared 3D web spaces. Using ActiveWorlds™ (AW) technology, we have been helping and observing children from different schools to synchronously navigate, create and communicate in virtual worlds. We have extended the functionality of AW by creating a simple building tool using C based Bot and CGI technologies. We have also added to the communications facilities of AW by integrat...