I once had a resident run through differentials for abdominal pain/symptoms in different ages (you're going to think differently about it in a 2 yo vs a 16 yo). I thought that was great and it was helpful when the students were asked to come up with differentials in each age group.
Antibiotics are still pretty confusing to me, so any chance I can get to go over those is very helpful.
Management of electrolyte disturbances is helpful: SIADH, DI, what do you do when you see a kid with a K of 8, etc.?
I'm in the PICU now, and had some great run-throughs of the different agents we use as pressors, ionotropes, etc, and what dose regimes we get different effects: ex. dose range of epi being primarily beta vs. when alpha comes in. When would you use dopamine vs. epi vs. dobutamine vs. milrinone vs. phenylephrine, etc.
Also, I had a great run through of airway issues with an attending: What different types of retractions correspond to. Why you see different responses to airway issues in different ages: ex. nasal flaring in little kids because the relative increase in the cross-sectional area of their nares from flaring can buy a lot less resistance to flow. Why you see head-bobbing. Stridor vs. stertor. If you really want to, go into laminar vs. turbulent flow and Reynold's number. What are indications for intubation?
