One word - Limericks ^^ (of a gender-changy sort or if you have one that isn't, it's ok)
They usually run 9 to 11 syllables for two lines (there's more technical terms but they always confused me)
Then two lines 5 to 7 syllables
And an ending line of 9 to 11
The two beginning lines and last lines rhyme. And the shorter two lines have a different matching rhyme
or AABBA (A being one rhyme and B being another)
EX
The limerick packs laughs anatomical
Into space that is quite economical.
But the good ones I've seen
So seldom are clean
And the clean ones so seldom are comical.
And also
There once was a man from Nantucket
Who kept all his cash in a bucket.
But his daughter, named Nan,
Ran away with a man
And as for the bucket, Nantucket.
But do keep in mind fund is more important than structure...like so...
A decrepit old gas man named Peter,
While hunting around for the meter,
Touched a leak with his light.
He arose out of sight,
And, as anyone can see by reading this, he also destroyed the meter.