a. Determine an explicit expression, a recursive process, or steps for calculation from a context.

Given a particular description of a problem or situation, students should be able to come up with a function that describes the relationship between two variables. This entails actually writing down an equation such that some variable y is expressed in terms of f(x) given only a description of the situation. Students should then be able to use that function to calculate a desired value.

For instance, given the right information, students should be able to write a function describing the number of Backstreet Boys concert tickets they can buy depending on how many chores they do around the house. So if students do a certain number of chores, they should be able to calculate how many tickets they can buy. Although...do they really need more than one ticket?