Learn to take responsibility of things that matter to you. The idea of making a song or poem with your key-phrases is awful honestly. You have three wallets as you mention OP, so are you planning to make three songs for them, what if you mix up the key-phrases? What if the kids mix up the words?

But my main point is, you can make songs about your key-phrases and teach them to kids, while you can write them down, find a safe place to store them. For me making a song and teaching it to kids is more hassle than saving the key-phrases in a safe place.