Mathematical Emphasis
Investigation 1—Exploring Numerical Data

• Collecting data
• Keeping track of data
• Organizing numerical data
• Creating representations
• Seeing representations as a way of communicating with others
• Describing and interpreting representations

Investigation 2—Teeth Data

• Collecting numerical data
• Organizing and describing numerical data
• Focusing on important features of data (range, unusual pieces of data)
• Representing the same data set using different materials
• Comparing data sets
• Interpreting data and making hypotheses based on data

Tips For Helping At Home
Questions To Ask:

• What is the problem about? Tell me in your own words.
• What did you do in class to get started?
• Can you make a drawing (model) to help you figure out the problem?
• What have you already tried? What steps did you take?
• What do you need to do next?
• Can you show it in a different way?
• How did you get your answer?

Helping At Home

• During this unit, your child will be collecting information and learning to represent it in different ways. Talk with your child about the kind of data he/she is collecting at school. Let him/her teach you one way to show that data.
• As you are reading the newspaper or a magazine, point out various graphs and charts to your child and talk about how you make sense of them, what they mean, and why you are interested in them. This is an opportunity for you to show your child how graphs communicate important information to you and your family.

Vocabulary Terms

Data

A collection of information

Line Plot

A number line with data individually represented above corresponding numbers

Mode

The point with the most data

Numerical Data

Data that is represented by numbers through measuring or counting, usually answers the question, “How many?”

Range

The difference between the highest and lowest values of data

Representation

A graph, picture or chart showing the data that was collected

Mathematics Vocabulary Web site

Mathematics Strategy—What Do Students’ Representations of Data Look Like?

As children begin to organize and represent data, it is important to be supportive of what they are representing rather than focus on what is missing or not represented. Don’t expect that all children will create the same graph or that it will look like a conventional bar graph. At this age, many representations will be original and unconventional. If a graph is unclear, ask your child to explain what he or she is trying to show.

Second grade students will tend to create data representations that focus mostly on the data they have rather than including all numbers in the range. Another common feature is that data is often grouped but may not be arranged in order. The examples below show ways some second graders represent data.

Pizza — This child showed a collection of answers for the question, “How many pieces of pizza do you eat for dinner?” Data is represented in a list but not organized or grouped. A question for this child might be, “Is there any way we could put these answers into groups that would make it easier to understand?”

This child represented data that answered the question, “How many teeth have you lost?” Data was represented in a number table that is grouped and ordered even though not all numbers are represented. A question for this child would be, “Where would you record data for a child who lost two teeth?”

Pets — This child represented data that answered the question, “How many pets do you have?” Answers were grouped together by number including children who had no pets. Although data is grouped and ordered, this representation is more a list than a graph. This child has the idea of grouping and organizing data and will be ready to start putting data into a line plot.

Source: Investigations in Number, Data, and Space: How Many Pockets? How Many Teeth? Dale Seymour, 1998. (Pages 18 and 19)

Mathematics Game—Fish For Tens, Second Grade Review Game

A mathematics card game based on the traditional game of “Go Fish.”

Materials

Deck of Number Cards 0-10 (four of each, remove wild cards)

Players: 2 to 4

Playing the Game

1. The object of the game is to get pairs of cards that total 10. Each player is dealt five cards and the rest are placed face down in the center as a draw pile.



2. If players have any pairs of cards that total 10, they are placed in front of that player and those cards are replaced with cards from the deck.



3. The person to the dealer’s left starts and asks one other player for a card that will go with a card in his/her hand to make 10.



4. If that player gets the card, the pair of cards is put down and one new card is drawn from the deck. This turn is over.



5. If that player did not get the card to make a ten, he/she takes the top card from the deck and that turn is over.



6. If the card drawn from the deck makes 10, the pair is put down, another card is drawn and that turn is over.



7. If a player runs out of cards but there are still cards in the deck, that player draws two more cards.



8. The game is over when there are no more cards left. The person with the most pairs wins.

Get to Number Cards (for printing)