The teacher needs to reaffirm that the Web project's success depends on all students doing their parts. Willingness to rely and trust in other team members - The nature of online projects requires that everyone share in the effort. Trust is developed when team members deliver or complete their tasks on time. If a student is having a difficult time completing a task, encourage him or her to ask for help. The group may also need to reevaluate the feasibility of the project.
Some projects sound great as ideas, but prove to be almost impossible in practice.
Once again these are all suggestions and each team is going to find their own best way to work together. The key is to openly discuss from the beginning how the team will work together. As you are building a strong foundation for your student teams, you'll also want to be looking at providing them a safe environment from which to work.