I've found that a lot of success for introductory advanced math hinges on getting students to feel comfortable talking about their math ideas and actually having a discussion wherein they can start to develop an awareness of how to precisely express what they do and don't know.For example, in an RA course I once took, we were put into study groups and had a (twice) weekly GoogleDoc discussion of the problem set.
So maybe one thing to do would be to model some problem set discussions early on in the semester with a Fishbowl discussion strategy (maybe use some of the stronger students or call in a couple of grad students). Then, monitor how the groups are doing on their independent GoogleDocs and pull out exemplary segments to analyze in detail in class.
As for other resources, I've found the early portions of Frank Morgan's "Real Analysis" have a simple conversational tone that's pretty good for developing baseline intuition about how unexpectedly weird the Real Numbers can be once you delve into their structure past what's necessary for basic arithmetic.