Views one to many relationship, display many records in columns
How about using the viewsfield module? You can try solving your problem by creating two views A and B, such that - 


View A excepts an argument 'ID' and lists all the marks associated with it, by having only the 'marks' field included for display/output.
View B has an ID field, a session field, and a viewsfield. In this third field the view A is embedded.


I hope this helps. I have not tried this, but I am reasonably sure it should help if the module is doing what it promises to do.