## Family Portraits: Comparing Function Families

By gathering data and continually translating among tables, graphs, words
and equations, students gain a deep understanding of different ways functions
can behave. Students review what they have learned about linear functions
and are introduced to quadratic and exponential functions. By unit’s
end, they create their own reference guide to direct variation, inverse variation,
linear functions, quadratic functions, and exponential functions. This final
unit is a summary unit for the 8th grade year.

### NCTM standard: Algebra

- Understand patterns, relations, and functions
- Represent and analyze mathematical situations and structures using algebraic
symbols
- Use mathematical models to represent and understand quantitative relationships
- Analyze change in various contexts

### NCTM standard: Number and Operations

- Understand numbers, ways of representing numbers, relationships among
numbers, and number systems
- Understand meanings of operations and how they relate to one another

### Primary Mathematical Goals

- Graph quadratic functions
- Compare equations and graphs that represent direct variation and inverse
variation
- Use scientific notation to represent very large and very small number
- Use laws of exponents