One of the most important aspects of early music appreciation and education is the understanding of musical form. While the concepts of structure within music may seem like complicated ideas for children to gain a mastery of, basics of formal analysis can be presented to children using techniques and examples on their level. Doing so is an excellent way to enhance the listening experience for young musicians while preparing them for more complex types of analysis in years to come.
Explain the basic concepts of form. Tell the children that sometimes, a song or piece of music gets divided into different pieces and that some of those pieces sound the same or similar to each other.
Teach them verse/chorus structure using a classic American popular or folk song. (A highly repetitive song like "Home On The Range" is an excellent example.) If the child is old enough to read, show him a printout or projection of the lyrics, so he can see how the different sections are organized.
Explain letter name form. Using the same folk song, point out "A," "B," and "C" sections. Point out when these points repeat.
Use visual aids. Drawing simple line graphs on the chalkboard, or just writing the letters "A," "B," and "C" in big letters, point to these, while listening to the folk song, and indicate which section is currently playing.
Introduce children to classical instrumental forms using storytelling. Without lyrics, it can be difficult for children to differentiate between different sections within a piece of music. Make up stories that correspond to different pieces and illustrate the changes in form. Use Mozart sonatas and concertos as an example, or show children the movement of Beethoven's 6th Symphony as it's animated in the original Disney film "Fantasia" (each section of the movement has different creatures or a drastic change in the storyline).