It is no secret that children love songs. Early in my career, I tried to get young children to expand their taste to at least the Beatles and maybe the Beach Boys. Most of them were not having it. Kids are going to like what they are going to like. Fortunately, many songs that children love in English also have Chinese versions. It helps to teach them songs that they already know so that they 1., are more interested in them, and 2., are more likely to grasp the meaning.
Most children already know the song Old MacDonald Had a Farm, which makes is a great candidate for a song to learn in Chinese. Old MacDonald is Old Mr. Wang in Chinese. I like this version of the song because it has the lyrics in pinyin and characters.