We have a co-ordinator who receives our work, they put it into an assigned box (like an individual inbox) with our names on it , then it is our responsibility to check regulary and collect any work assigned. Then when we've done the work we put it into another box the 'out box' which is the same for all people doing DE. The co-ordinator checks it off (that we've handed, what title page it is and the date it was handed in and sent) and then it gets sent away.
I would think it is you're responsibility to check and collect your work. But for assessments you should be notified by the co-ordinator of the requirements and dates etc.
This is how they did it at my school anyway it might be different for you so you should check with your co-ordinator. Also good luck with it, DE may seem hard at times but you get used to it and can end up with some really good skills.