Please, Sir

Please sir, please sir, it's not an excuse:
My dog ate my homework, I'm telling the truth.
I slept at a friend's house and I took it there with me,
So now I find I've left it. Oh, what a silly me!

Please sir, please sir, it's not an excuse:
I've got the wrong book, sir, I'm telling the truth.
I left it on the table, the baby got it, too;
My younger sister nabbed it and flushed it down the loo!

I'd never tell you lies, sir, you should know that,
But I haven't done my homework - I'll blame it on the cat!
Last night while I was sleeping, a ship came from the sky,
A light shone on my homework and took it way up high.

Please sir, please sir, I know it sounds real daft:
I haven't done my homework - you know that as a fact -
But can you really blame me? The laws of physics stink!
And can you really tell me: Should I see a shrink?