My son has been potty trained since december of 2005, like when he was 33 months old.

most kids especially at this age are amazed by it as they had it in nappies for so long that they wonder what it is.. my 11 yr old son still gets caught playing with it ... all the specialist tell you that its good for men and women to masterbate themselves and if stop our kids doing it and teach them its wrong to do then we can be affecting them in future... i don't know if that is true or not we just tell him there is a time and place you want to do that do it in your room or the toilet were no one has to see it..... plus make him go wash his hands... though we have said leave it alone it will fall off when we are in the shops and catch him doing it... normally i say it quietly but hubbie likes to try embarass him into stopping by yelling it out.... have to admit haven't noticed him doing it for awhile so might have worked lol

anyway wouldn't stress and if you are out and about and he playing with it just say oh must need the toilet as its also natural to grab there when they need toilet so just let everyone around you think its just that needs toilet......

Of course its normal, but that doesn't mean that we as parents should not teach our children when it is appropriate and where its appropriate, men playing with themselves in baseball or anywhere is not the most wonderful sight, a gentleman will not have a good old feel or scratch in public.  So as innocent and as young as they may be it doesn't mean they cant be taught right from wrong.