I disagree about ornamentation..... I teach them it from the start...easy stuff.... play twinkle twinkle with "cuts" or "slides".... gets them used to it, and it isn't nearly as big a hurdle later on... (plus it makes the tunes sound more "Irish"). There is a great whistle tutor online Mike Simpsons whistle page, but he assumes that you read music.... but a lot of the advice is great....Playing the whistle really is easy (I know... easy for me to say when I've been playing it for so long)...... it is being able to use the ornamentation well that makes the difference between an ordinary whistler and a good one.
Oh rhythms are easy to remember
Reels are Wa-ter Me-lon
Jigs are Pine-app-le Ap-ri-cot
slainte
alison