The metric system, based on powers of ten, uses prefixes to describe measurements of all sizes. This video introduces students to the metric system’s prefixes and some of the more common bases. The mnemonic “King Henry Died Drinking Chocolate Milk” gives students a funny, memorable way to keep the prefixes straight. The song includes an explanation of the following prefixes: kilo, hecto, deca, deci, centi, and milli.

*You know, I figured out how to memorize the metric system. It’s all based on powers of ten. So you just need to memorize a couple Latin prefixes and then you can measure anything. Just remember King Henry. Oh, you don’t know about King Henry? Listen up:*

King Henry Died Drinking Chocolate Milk,

King Henry Died Drinking Chocolate Milk,

King Henry Died (Base!) Drinking Chocolate Milk,

King Henry Died (Base!) Drinking Chocolate Milk!

It goes: Kilo, Hecto, Deca, (Base!)

Deci, Centi, Milli, wait.

Kilo, Hecto, Deca, (Base!)

Deci, Centi, Milli.

King Henry ordered cocoa by the kilogram,

That’s 1000 grams, we could barely fit it in the van.

The driver drove over a hectometer,

100 meters, with no AC in a two seater.

I was feeling like a joker in a deck of cards,

Milking cows by the decaliter in the barn.

10 liters at a time, when I

Saw the van driver and gave her a piece of my mind.

I whispered at a decibel,

^{1}⁄

_{10}of a bel,

Saying that King Henry wasn’t checking his health.

She made her fingers small like a centimeter,

^{1}⁄

_{100}of a meter, and said, please believe her:

“If he gets this much bigger, he might explode.”

I agreed, even a milligram of cocoa,

^{1}⁄

_{1000}of a gram, might change the throne,

'Cause hot chocolate can make a king turn cold.

King Henry Died Drinking Chocolate Milk,

King Henry Died Drinking Chocolate Milk,

King Henry Died (Base!) Drinking Chocolate Milk,

King Henry Died (Base!) Drinking Chocolate Milk,

It goes: Kilo, Hecto, Deca, (Base!)

Deci, Centi, Milli, wait.

Kilo, Hecto, Deca, (Base!)

Deci, Centi, Milli.

*
King Henry Died Drinking Chocolate Milk
*
isn't just a funny sentence--it's a memorable way to keep the metric system's prefixes straight. Listen to this song a few times and you'll have them memorized, no problem.

These Latin prefixes are the same when used with any metric unit of measurement. Each prefix signifies a different ratio to the base unit, from 1000 times the base to

^{ 1 }⁄

_{ 1000 }of the base. And there are even more. Smaller prefixes include

*nano*and

*micro*, while large prefixes include

*mega*and

*giga*which you might recognize from the tech world.

When talking about the base units by themselves, no prefix is used. The most common bases in the metric system are meters, liters, and grams. Meters measure distance, liters measure volume and grams measure mass.

*
Kilo
*
is the prefix used to signify 1000 of the base unit. A kilogram is 1000 grams and a kilometer is 1000 meters.

*
Hecto
*
is the prefix used to signify 100 of the base unit. A hectogram is 100 grams and a hectometer is 100 meters.

*
Deca
*
is the prefix used to signify 10 of the base unit. A decaliter is 10 liters and a decameter is 10 meters.

*
Deci
*
is the prefix used to signify
^{
1
}
⁄
_{
10
}
, or 0.1, of the base unit. For example, a decimeter is
^{
1
}
⁄
_{
10
}
of a meter.

*
Centi
*
is the prefix used to signify
^{
1
}
⁄
_{
100
}
, or 0.01, of the base unit. For example, a centimeter is
^{
1
}
⁄
_{
10
}
of a meter.

*
Milli
*
is the prefix used to signify
^{
1
}
⁄
_{
1000
}
, or 0.001, of the base unit. For example, a milliliter is
^{
1
}
⁄
_{
1000
}
of a liter.