LESSON 3 Volume vs. Number

Planning the Experiment

Mrs. Dewey's class is playing the game Fill It First using marbles. Frank and Nicholas are on one team, and Jackie and Maya are on the other team. Jackie and Maya are winning because they have been able to correctly predict the volume of the marbles more often than Frank and Nicholas.

“We lost again. They sure are lucky!" said Frank. “Their predictions are right almost every time.”

“It may not be luck,” said Nicholas. “They may have a way to figure out what the volume will be.”

“How do they do it?” asked Frank.

“I don't know,” said Nicholas. “Maybe they follow a pattern.”

“I can't see a pattern on our score sheet. The numbers jump around too much,” said Frank. “Before we play again, let's make a table that can help us make better predictions. We can find the volume of different numbers of marbles and look for a pattern that can help us.”

“Won't that be cheating?” asked Nicholas.

“Not if we figure it out for ourselves,” said Frank. “We need to do something. Mrs. Dewey said that the next time we play the game, we are going to use a different-size marble. We'll have to think about the number of marbles, volume, and which marbles we're using. We'll never be able to keep all that straight.”