Large-scale cooperation support for learners becomes even more important, when e-Learning is implemented in scalable, open, dynamic and heterogeneous environment. We have designed grid architecture and implemented grid middleware and higher CSCW services for establishing collaborative platform for e-Learning. A Learning Assessment Grid, abbreviated as LAGrid, is built on top of these services. This paper introduces the layered LAGrid architecture and presents how to implement grid middleware to support collaborative platform for e-Learning using web services technologies. The work shows serviceoriented grid middleware layer provides a good middleware platform for collaborative applications in large-scale cross-organization environment.