## HSI.3 Exponential Functions I (A2)

### Billions and Billions

How has the human population changed over time? Students build an exponential model for population growth, and use it to make predictions about the future of our planet.

Topic: Building Functions (BF), Interpreting Functions (IF), Linear, Quadratic, and Exponential Models (LE)

### Green Acres

How has the urban population changed over time, and will we all eventually live in cities? Students use recursive rules along with linear and exponential models to explore how America's urban areas have been growing over the last 200 years.

Topic: Interpreting Functions (IF), Linear, Quadratic, and Exponential Models (LE), Reasoning with Equations and Inequalities (REI)

### iPod dPreciation

How has the iPod depreciated over time? Students compare linear and exponential decay, as well as explore how various products have depreciated and what might account for those differences.

Topic: Creating Equations (CED), Interpreting Functions (IF), Linear, Quadratic, and Exponential Models (LE)

### I Remember

How much can you trust your memory? Students construct and compare linear and exponential models to explore how much a memory degrades each time it's remembered.

Topic: Interpreting Functions (IF), Linear, Quadratic, and Exponential Models (LE)