Songs: Camptown Races, For he’s a jolly good fellow, Summertime.
Remember to divide the songs and exercises into smaller parts (even if you have to divide it into 3 or 4 notes per part). The important is to give time to your body to develop the muscle memory necessary. It takes time. So practice it slowly and for short periods of time in the beginning.
15 minutes practice with your full attention is much better than an hour without focus.