This lesson introduces students to function notation. Students encounter situations in which referencing certain functions and their inputoutput pairs gets complicated, wordy, or unclear. This motivates a way to talk about functions that is more concise and precise.
Students learn that function notation is a succinct way to name a function and to specify its input and output. They interpret function notation in terms of the quantities in a situation and use function notation to represent simple statements about a function. The work in this lesson prompts students to reason quantitatively and abstractly (MP2) and communicate precisely (MP6).
Lesson overview
 2.1 Warmup: Back to the Post! (10 minutes)
 2.2 Activity: A Handy Notation (15 minutes)

2.3 Activity: Birthdays (10 minutes)
 Includes "Are you Ready for More?" extension problem
 Lesson Synthesis
 2.4 Cooldown: A Growing Puppy (5 minutes)
Learning goals:
 Interpret statements that use function notation and explain (orally and in writing) their meaning in terms of a situation.
 Understand that function notation is a succinct way to name a function and specify its input and output.
 Use function notation to express functions with specific inputs and outputs.
Learning goals (student facing):
 Let’s learn about a handy way to refer to and talk about a function.
Learning targets (student facing):
 I can use function notation to express functions that have specific inputs and outputs.
 I understand what function notation is and why it exists.
 When given a statement written in function notation, I can explain what it means in terms of a situation.
Glossary:
 function notation  Function notation is a way of writing the outputs of a function that you have given a name to. If the function is named \(f\) and \(x\) is an input, then \(f(x)\) denotes the corresponding output.
 Access the complete Algebra 1 Course Glossary.
Standards:
 This lesson builds towards the standard: CCSS.HSFIF.A.1MS.FIF.1MO.A1.IF.A.1bMO.A1.IF.A.1a
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