“The part of the assessment that really was challenging was the peer evaluation part. It was extremely difficult to assess each individual person’s contribution to their project based solely on their portion of the presentation.” I agree with this and for this reason think its best to allocate group presentations group marks, although the feedback on individual performance in the presentation can be individualised. if an individual mark is required then I find it works if you add a separate but related, assessment activity. Ive described an example here: http://octelreflections.wordpress.com/2013/05/21/approaches-to-assessment/