Database Design Question

Hi,
I've been tasked with coming up with a project/time tracking system. A technician can be assigned a task to perform and upon completion of the task the technician enters the date, amount of time it took to complete and a description of the work done. Also, the system must be able to accomodate a higher lever "project". Time can be associated directly to a project or a project can contain any number of tasks, each with its own time entry. A task can only have one project parent, though. A project can have many child tasks.

I'm sure this is an elementary excersise for many of you but I'm fairly new to database design and want to get started in the right direction.

I'm looking for a clean database schema that can accomodate these data requirements.

Any help would be greatly appreciated.

Thanks,
crowma

Take a look at the schema of TaskFreak for ideas.

Maybe a good idea to include the functionality of Time Tracker too?