- Compute with whole numbers, fractions, decimals, integers, and rational numbers
- Develop, analyze, and explain procedures for computation and techniques for estimation

*Benchmarks* 12B (Habits of Mind: Computation and Estimation)

Grades 3-5, page 290

Add, subtract, multiply, and divide whole numbers mentally, on paper,
and with a calculator.

*Benchmarks* 12B (Habits of Mind: Computation and Estimation)

Grades 6-8, page 291

Use ratios and proportions, including constant rates, in appropriate
problems.

*Benchmarks* 12B (Habits of Mind: Computation and Estimation)

Grades 3-5, page 290

State the purpose of each step in a calculation.

- Develop, analyze, and explain methods for solving proportions
- Select and use an appropriate method for computing from among mental arithmetic, paper-and-pencil, calculator, and computer methods
- Use computation, estimation, and proportions to solve problems
- Use estimation to check the reasonableness of results

Grades 3-5, page 296

Make sketches to aid in explaining procedures or ideas.

*Benchmarks* 12D (Habits of Mind: Communication Skills)

Grades 3-5, page 296

Write instructions that others can follow in carrying out a procedure.

*Benchmarks* 12B (Habits of Mind: Computation and Estimation)

Grades 6-8, page 291

Determine what unit (such as seconds, square inches, or dollars per
tankful) an answer should be expressed in from the units of the inputs
to the calculations, and be able to convert compound units (e.g., yen per
dollar into dollar per yen, or miles/hour into feet/sec.

*Benchmarks* 12B (Habits of Mind: Computation and Estimation)

Grades 3-5, page 290

Read and follow step-by-step instructions in a calculator or computer
manual when learning new procedures.

*Benchmarks* 12C (Habits of Mind: Manipulation and Observation)

Grades 3-5, page 290

Use calculators to determine area and volume from linear dimensions,
aggregate amounts of area, volume, weight, time, and cost, and find the
difference between two quantities of anything.

*Benchmarks* 12B (Habits of Mind: Computation and Estimation)

Grades 6-8, page 291

Insert instructions into computer spreadsheet cells to program arithmetic
calculations.

*Benchmarks* 12B (Habits of Mind: Computation and Estimation)

Grades 6-8, page 291

Decide what degree of precision is adequate and round off the result
of calculator operations to enough significant figures to reasonably reflect
those of the inputs.

*Benchmarks* 12B (Habits of Mind: Computation and Estimation)

Grades 6-8, page 291

Estimate distances and travel times from maps and the actual size of
objects from scale drawings.

*Benchmarks* 12C (Habits of Mind: Manipulation and Observation)

Grades 6-8, page 294

Use calculators to compare amounts proportionally.

*Benchmarks* 12B (Habits of Mind: Computation and Estimation)

Grades 3-5, page 290

Judge whether measurements and computations of quantities such as length,
area, volume, weight, or time are reasonable in a familiar context by comparing
them to typical values.