Also making sure that they are developing good hand position will help them when it comes time for chords. Keeping the thumb behind the second finger keeps the hand square. Also positioning the guitar in a better place and angle helps as well. I work with beginner students a lot in regards to the best positioning in the very beginning so that they don't develop bad habits that will hold them back in the long run.

All the best,
Joe Pinnavaia
http://www.youtube.com/user/rhinoguitar
http://www.digital-nations.com/artists/testtuberhino