The hardest things about learning this song are the frequent tied notes and syncopated rhythm. For beginner students who have very little concepts of counting quavers or syncopated rhythm, I tried to get them to learn the song aurally first. We would sing the songs several times and clap the rhythm together. Then I would get them to focus on reading the notes, and sometimes cross out the second tied notes to help young students to read better.
Feel free to download the file from below and enjoy learning/teaching this lovely song! :)