Rule Of Displacement(silver)

At school that day was water play
Mathematical talents they'd display,
measure this and test that out,
now what's displacement all about?

The problem was they had no clue
and didn't know just what to do.
An object of a decent size
would give them all a grand surprise.

Teacher told them find something
that would the level higher bring,
to push that water out the way
and view displacement on display.

So searching for a decent prop
something that would make a plop,
they couldn't find a thing to use
and put them downright in the blues.

One student happened to be late
and had the others most irate,
when suddenly the idea dawned
this one would be Displacement's pawn.

They grabbed her quickly, shoved her in
and saw the water start to spin,
they saw that water surge up quick
this object really did the trick!

But yelps and hollers met their ears
as student made it very clear,
a fright she got, the water cold
she sure was a sight to behold!

Displacement now they understood
but teacher yelled they never should,
do such a thing to anyone
even if it was in fun.

The first rule they must understand
was first to ask and not demand.
But in then end they all did laugh
completing their Displacement graph!