Liz S. is so right about whining. Teach the correct way/tone of voice to make a request. Then keep reminding, and reminding – it will take awhile, because ALL kids whine. It's as automatic a response as giggling is, and all of us did it to our parents. ;-)
The other thing that helps with whining is for parents to politely request what they want of their children. I'm often startled to hear the way moms or dads or older siblings boss little kids around. Snappish, rude, abrupt. I wonder how surprised we'd all be to hear a candid recording of our interactions with our kids. It's worth being aware of, because kids learn by example to a far greater degree than through what we tell them.
Finally, for moms who choose to employ time-outs for discipline, there's a set of guidelines that will help make them positive. The ideal is to help a child learn to control himself, not to be controlled by outside forces (even if the force is a well-intentioned parent).
Ideally, a time-out is NOT PUNISHMENT, and therefore, it's not important that the child sit quietly for the full minute-per-year. It is only important that he realize that he must be in control of his emotions/behavior to continue his play. (Of course, this will take practice. None of us change instantly.)
Once a power struggle ensues – in which a parent repeatedly drags a child back to the time-out spot to start the clock again, the exercise becomes punitive (to both parent and child, actually). The original point of the time-out has been completely lost on the child, and he just feels the whole thing is unfair. So he ramps up his emotions and resistance.
Now it's merely a power struggle, an entirely different dynamic than "Let's give you some time to be in control of yourself." Instead, it has become, "I need to conquer you." This is really unacceptable news for a normal, spirited child, and is essentially unfair, because the child had no possibility of avoiding consequences for parental decisions made on the spot.
So, the ideal time-out gives the child a minute or so to calm down, perhaps realize his behavior was undesirable, so that he can re-set himself and resume his play. And with the ideal time-out, the child is more likely feel protected and assisted in his growing up, not embroiled in a continuing power struggle that leaves bad feelings for him to deal with.