- Collect, organize, and describe data

Grades 6-8, page 229

The larger a well-chosen sample is, the more accurately it is likely to represent the whole. But there are many ways of choosing a sample that can make it unrepresentative of the whole.

- Construct, read, and interpret displays of data

Grades 3-5, page 296

Use numerical data in describing and comparing objects and events.

Grades K-2, page 211

Simple graphs can help to tell about observations.

- Formulate and solve problems that involve collecting and analyzing data

Grades 3-5, page 228

Spreading data out on a number line helps to see what the extremes are, where they pile up, and where the gaps are. A summary of data includes where the middle is and how much spread is around it.

*Benchmarks* 9D (The Mathematical World: Uncertainty)

Grades 3-5, page 228

A small part of something may be special in some way and not give and
accurate picture of the whole. How much a portion of something can help
to estimate what the whole is like depends on how the portion is chosen.
There is a danger of choosing only the data that show what is expected
by the person doing the choosing.

Benchmarks 9C (The Mathematical World: Shapes)

Grades 3-5, page 223

Graphical display of numbers may make it possible to spot patterns
that are not otherwise obvious, such as comparative size or trends.

*Benchmarks* 9D (The Mathematical World: Uncertainty)

Grades K-2, page 227

Often a person can find out about a group of things by studying just
a few of them.

*Benchmarks* 9D page 227 (The Mathematical World: Uncertainty)

Grades 3-5

Some predictions can be based on what is known about the past, assuming
that conditions are pretty much the same now.

- Explore concepts of chance

Grades K-2, page 222

Some things are more likely to happen than others. Some events can be predicted well and some cannot. Sometimes people aren’t sure what will happen because they don’t know everything that might be having an effect.

*Benchmarks* 9D (The Mathematical World: Uncertainty)

Grades 3-5, page 227

Statistical predictions (as for rainy days, accidents) are typically
better for *what proportion* of a group will experience something
than for which members of the group will experience it and better for *how
often* something will happen than for *exactly when*.

*Benchmarks* 9D (The Mathematical World: Uncertainty)

Grades 3-5, page 228

Summary predictions are usually more accurate for large collections
of events than for just a few. Even very unlikely events may occur fairly
often in very large populations.