My farewell is coming in a few months, and i thought i would play an instrumental on the day, just for the fun of it.
So my idea was to have a song, where there are 3 parts, each signifying a stage in school life.

1. When you enter school you're extremely scared and worried. So this part would be on those lines
2. As time progresses, school gets more and more fun, and you begin to enjoy it. So this would be a happy and fast part.
3. At the end, you just have to leave no matter what. Thus, this would be a sad and lonely part of the song.
The song will end very abruptly, signifying how school suddenly gets over.

Im basically trying to create a song on those lines. I'd like your opinions on how it is and whether its a workable song.
I would also like to know what kind of scales I should use for every part (important) and how i can create a kind of illusion using certain techniques(specify which).
Along with me(lead guitars) i'll have a friend on either bass or rhythm and another on keyboards.

Your ideas and opinions are appreciated!!!
Thanks in advance.
use modes i think, aelion for number 1, lydian for 2 and phrygian for 3, somewhere along thoes lines will get you something nice. or just play ard with diffent scales and stuff like harmonic minor or even pentatonics.

in general major scales will give out a happier mood while minor scales will give out a sadder mood so just mix em up