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How much food do your classroom animals or household pets eat every day?

Does the guinea pig eat a spoonful of pellets?

handful?

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Can you compare how much you eat with how much your dog

eats?

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A shrew eats as much as one hundred times its own

weight in food in one day.

If you ate one hundred times your weight, how much food would you consume in a day?

How many times your present weight will you eat in twenty years?

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Formulas and recipes

Formulas given in parts also emphasize the need for establishing some arbitrary standard unit and for selecting a unit of an appropriate size for the purpose intended. (If you want to end up with a pailful, you will not want to measure it out in tablespoons.) Almost any kind of container can serve as a standard, provided it is filled to the same level each time it is used. Play-Doh, baker's dough, finger paint, and papier-mâché are a few examples of concoctions children can measure in this way. Older students might like to try following this formula for a chemical garden:

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When asked how many children using the same-sized cup
could be served from a gallon jug, a youngster in third
grade held the cup up against the bottle and proceeded
to mark off how many times the cup fitted into the
height of the bottle.

"Three," was her answer.

"Only three children from the whole bottle?" asked the teacher.

"Yes," replied the girl, holding the cup up to the
bottle again, "Three children."

After the child had poured out two cupfuls, making
scarcely a dent in the contents of the bottle, the
teacher asked the girl what she thought now.
The child clung to "Three."

It was not until the third cupful had been emptied out
that she looked at the bottle which was still almost
full, and said, "I guess it's more than three."

How much punch will you need to make to provide for refills at your party?

What if there's some punch left over? Can you pick out
a container that is just about the right size to hold
what's left?

Try finding a container of the right size for all sorts of leftovers: clay, crayons, marbles, etc.

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Dis

Cups, pints, quarts, and gallons become real to the child as he handles them. tinguishing one quantity from another becomes important to him when there is reason for telling them apart.

Children in a second grade set about the task of changing
the water in their fish tank. The teacher reminded them
that tap water must be treated with conditioner before
it is added to a tank. The directions on the back of the
bottle of conditioning tablets called for one tablet for
each gallon of water.

Although most of the children knew the word "gallon,"
none of them had any idea of the amount it stood for or
of how to go about getting it. After rummaging through
a variety of containers around the room, someone came
up with a milk carton marked "one half-gallon." Putting
their heads together, the children came to the conclu-
sion that two half-gallons would make one whole gallon.
From there they went on to find out how many gallons it
took to fill the bucket in which they mixed the condi-
tioner, and how many buckets it took to fill the fish
tank.

How many different ways can you find to make a gallon?

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In one trial class, a group of students became interested
in making bread. To produce a loaf of bread good enough
to eat requires careful measurement of volume, tempera-
ture, and time. The making and baking of loaves that

were eatable and loaves that were not taught the young
bakers a lasting lesson about the usefulness of measure-

ment.

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