According to Mordechai

This is how it works: There are three books. One is for mal'achim (angels) and they for sure get a sweet new year. One is for resha'im (wicked people) and they don't get a sweet new year. And most of us are in the middle book. We sometimes do mitzvos and sometimes do aveiros. If we daven and do teshuva we'll get to the book for a sweet new year. If not, chas v'shalom, we go to the book for not a sweet new year. But children don't have to worry so much 'cause this is mostly for grown-ups.