It is possible to interest toddlers in the piano, but you will have to trim your expectations accordingly. If one thinks of "regular piano" as difficulty level 3, then "preschool piano" is difficulty level 2 (easier) and the toddlers use difficulty level 1. Thus, you should make piano for toddlers as easy and appealing as possible. You can get many opinions, but my experience leads me to tell you that almost all you can accomplish with piano for toddlers is to get them to enjoy the experience of sitting at the piano. Forget curriculum. Can you get toddlers to see the piano as a fun toy, and you, the teacher, as the ringmaster of a fun musical circus? Banish guilt, homework and frustration from your teaching. With toddlers, everything that matters is NOW. If you confuse them with expectations, expect disaster. And with toddlers at the piano, one disaster and it's over: they may never want to go to the piano again. This is based firmly on experience. I teach piano to kids in their homes, often to children who have younger, toddler siblings. These toddlers watch the lessons with great interest. As long as their brothers and sisters seem to be having fun, it is almost irresistible to the toddlers. They want to get involved as long as you can bring it down to their level. All the toddlers I have taught are younger siblings who waited for the moment when I turned to them and said, "Would you like to try it?" They have seen my silly antics with the older kids, and want to get in on the noisy musical fun. So I sit them down on the bench, making sure they do not fall off. Piano benches are often slippery and the littlest kids can plummet off the bench in an instant. Keep your eyes open for this. I generally start by trying to get them to play Middle C, or what we call "number one." This in itself is not an easy task for a toddler, so be absurdly gentle. They may not be able to do anything you ask, but never react as if they have disappointed you. Remember, the first step for a toddler at the piano is to enjoy sitting there, so don't scare them off. In fact, most of the time they will wildly bang the keys. After years of speculation, I have divined what this means. Kids who cannot concentrate enough yet bang the keys because, to them, that is what they see a pianist do. They want to do the same. Let them do it, and then quickly ask again, "Let's find that note in the middle, again. If we play it, cheese might explode from the piano!"" You will find that if you never are impatient, you will get them to find that note. If they don't, keep trying later. Success matters far less than mood. The most important habit to learn at the piano is that it is fun. Until you have learned that, there is nothing you can learn.