I think that music may have a limited role in the 'lecture' class where I like to encourage students to be part of discussion and to participate in lecture (when surveyed they claim to learn characteristics of materials better from lecture than from reading on their own). Their favorite activity is the field trip and here too I think that music has a limited role to play; it's a little rude to have your ear buds in when someone from industry is taking time out of their business day to share information with you. Doesn't hearing music takes up 'processing' power in you brain? Is it perhaps a distraction in some instances?