What exactly do you mean by "elements of music"?
Is that like the concept areas like structure, pitch, duration, tone colour, texture and dynamics/expressive techinuqes or something else? Or just anything to do with the music.
I don't realy know much about this stuff or Cats or anything -
The way i'm interpreting what u said is u have to give a talk on a particular Broadway musical is that right? and how the music in it is composed etc.
Or would you be looking at Andrew Lloyd Webers music more in general?
Probably the best way to look at it would be to listen to a couple of the main pieces and find information that way.
eg. Macavity uses influences of jazz, including swing. Instrumentation is also commonly used in jazz - piano/drumkit/bass/vocal, with some trumpets .. maybe trombones sax as well? Begins with an ostinato in the bass which continues through the piece. (Goes something like, C, C,Eb, Eb,F, F#G) Maybe mention what form its in. (is it in verses!?)
I'm pretty sure macavity is based on a C Blues scale - perhaps you could look up the chord structure of that.
Is that the kind of thing u need to talk about =S If not just ignore me! im nuts
But yeh look at stuff like the phrasing ie. how many phrases or verses there are... any repetition.. perhaps you could look at the use of lyrics as well, how the music is used to evoke the emotion of the lyrics - ie. the syncopation in jazz helps to create suspense = mystery! any use of pauses or sustained notes also would add to that. hmmmm
cya ! xoxo