Think you have a good memory? Try this test and see. I have used this as an actor warm up AND as punishment for unruly "boys and girls." Most people have it memorized after the first time through, but I have seen it take as long as 3 days.
Have your "pupils" repeat each item back to you in order. For example first it's ONE hen, then it's ONE hen, TWO ducks, ONE hen, TWO ducks, THREE squawking geese …and so on.
Good luck!!!

The Jerry Lewis Memory Test

One hen

Two ducks

Three squawking geese

Four limerick oyster

Five corpulent porpoises

Six pairs of Don Alvaso's tweezers

Seven thousand Macedonians in full battle array

Eight brass monkeys from the ancient, sacred crypts of Egypt

Nine apathetic, sympathetic, diabetic old men on roller skates who show a marked propensity towards procrastination and sloth

Ten lyrical, spherical, diabolical denizens of the deep who ho and fro around the corner and quo, quiver and quay, all at the same time!