I have more than 150 students using e.Portfolios and I struggle with finding different students' work. I ask students to name their GoogleSites specifically so I can sort them. I have created a form for student to complete to keep a record of the links. Maybe you have a better way?This was my suggestion for attempting to keep track of all the sites. (I used this method myself with about 100 students a few years ago).
To make it easier to sort submissions I create student groups (not for collaboration, just for sorting) and make a different form for each group. Students have to submit their updates to the form that is assigned to their group. That way instead of having 150 students making submissions to one form I have 25 students making submissions to each of six forms. It's a little easier to sort through 25 students making submissions than 150 students making submissions to one form. I make it the responsibility of the students to enter their submissions on the correct form.