homework upload facility for pupils

Hi - I run an extranet for the school I work at which uses the ning platform - www.woodleigh.ning.com . It features downloadable homeworks, sports teams lists, reading books, spelling lists etc. The parents have asked whether a facility could be added to allow pupils to upload their homeworks to the ning site (from home) so they could then print the homeworks the next day (at school) The catch is that they would want their homework to be viewable only to themselves and/or teaching staff, and not other pupils who might copy it. Or alternatively, if the uploaded homework could only be viewed by the teacher who it was sent to.

It is likely that most homework would be a word document file.

Any advice would be really appreciated.

Thanks