Well,
When your Tamagotchi turns into a child, shorlty after that, you will recieve mail that tells you that you are now ready for preschool. When you recieve the mail your Tamagotchi will leave and have an "Away" sign. When the away sign comes up, press the ( b ) button and it will show you what your Tamagotchi is doing. When you are away, you will see another Tamagotchi, (the teacher) that will give you a backback. Then you will come back. When you come back go to the connection icon and go to the work option. You will see your Tamagotchi leave and then see a sign saying "Away". Once more, press the ( b ) button. You will see your Tamagothi's teacher sing a song to yours, then you will sing it back. You will either fall on your face or get the song correct. It's so cute seeing your Tamagotchi interact with the teacher.
Hope I Helped,
Pupsluv24 ^_^