Functions Unit: Lesson #1

Goal:  Be able to pick out dependent and independent variables in a relationship, and be able to recognize functions/not functions from tables.

Skills addressed: Dependent and independent variables, Definition of relation and function.

Hard Parts: Understanding the definition of a function is subtle.

This can be addressed with a function/not a function series of questions. Use the “Would a robot be able to tell you the output?” idea as a question that students can ask themselves when considering whether a relationship is a function. Lots of practice in different contexts.

Dependent/independent isn’t so bad, since it fits very well with “Which quantity depends on which quantity?”

Good Questions:

“Which quantity depends on the other?”

“Find a relationship between two variables, where one quantity depends on the other.”

“Explain how the dependent quantity depends on the independent quantity.”

“If the independent variable is 7 can you tell me exactly what the dependent variable is?”

 “In this case, the “dependent” quantity can’t possibly only depend on the independent quantity. Explain how you know this?”

“Show me a table of a function, and show me a table of something that’s not a function.”

Hook: An EMusic account – subscription plus cost per song – to get a concrete model that students are familiar with. Problem is that Emusic doesn’t actually work that way. Turns out that you get a download limit. Still looking for something, but whether there exists anything doesn’t really matter.

Assessments: White board question, questioning, exit ticket

Activities: Lecture, Think pair share, Independent practice

Materials: Slides, Whiteboards, markers, Worksheet(?)

Homework: 1, 2, 4, 6 on

Notes: Maybe I need to hit relation harder.