Where I am rotating right now, the neighboring medical school has its students do two weeks of Anesthesiology during their M3 Surgery rotation. They all have their little procedure logs to keep track of successes and attempts at things like IVs, intubations, mask ventilations, and NG/OG tubes. They are also given a topic list to cover with their residents or attendings that include such things as cardiac drugs, local anesthetics, inhalational and IV anesthetics, NMB, card/pulm physiology, and anesthetic monitoring.
I strongly disagree with only allowing M3s to start IVs after induction, and disallowing intubation attempts. There is a time and place for learning these skills, and that is now.
As far as what skills to teach, I believe that the most important procedures for them to do on their brief stop-over with you are IVs and mask ventilation. The rest are gravy.
If you meet them in the afternoon, tell them when you set up, and ask them to help you get your room ready the next day. You can walk them through the check-off, and explain what drugs you are using, and why. During the cases themselves, take a few minutes and review some basic pharmacology as it pertains to the surgical patient. Talk a little about the vent (this is probably the only time they'll get any vent experience outside of ICU) and pulmonary physiology (PEEP, TV, EtCO2, etc).
Finally, just because they are brand new does not mean that they cannot be useful. At the very least, they can draw up drugs for you and can chart vitals once shown how. Challenge them a little, and offer a reward (a crack and intubating, perhaps), and you may be pleasantly surprised.
