Assisting Teacher Handoff Sheet

Session 1.2 - Evaluating Functions and Notation | Week 1, Thursday

FOR THE ASSISTING TEACHER: Read the information below before Kaa Shaayi leaves at 2:00. You are supervising worksheet time from 2:00-3:00. Students work independently from 3:00-3:30.

What Students Just Learned (30-second summary)

f(x) notation means "the function called f, evaluated at input x." It is NOT multiplication. To evaluate f(3), replace every x with (3) and simplify. The biggest pitfall involves negative inputs. Students must use parentheses: (-2)² = +4, but -2² = -4.

The Worksheet

Worksheet 1.2 (40 points, 10 problems across 4 parts + weekly reflection). The Quick Reference box at the top has a worked example and the negative-input warning.

Part A (Story): Cell phone plan cost function and candle business profit function. Students evaluate and solve real-world equations.

Part B (Visual): Reading function values from tables, combining functions, pattern recognition.

Part C (Traditional): Pure algebra - substitution into linear and quadratic formulas. This is where the negative-input errors happen.

Part D (Synthesis): Connecting all three lanes with f(x) = x² - 1, plus the Weekly Reflection (Problem 10, 5 points).

Top 3 Mistakes to Watch For

1. The (-2)² vs -2² confusion.
When students plug in -2 and see x², many compute -4 instead of +4. Remind them: "Put the number in parentheses FIRST, then do the math." The Quick Reference box has this spelled out.
2. Thinking f(x) means f times x.
If a student writes "f(3) = f · 3," they've misunderstood the notation. Redirect: "f is a name, not a number. f(3) means plug 3 into the rule."
3. Forgetting to distribute in Problem 4b: f(a+3).
f(x) = 2x + 1, so f(a+3) = 2(a+3) + 1 = 2a + 6 + 1 = 2a + 7. Students often write 2a + 3 + 1 (forgetting to distribute the 2).

If a Student Is Stuck

First: Point them to the Quick Reference box, which has a full worked example.

Second: For algebra problems, ask: "Did you put your number in parentheses before doing anything else?"

Third: The Session 1.2 Reading is in Canvas with more examples.

Video: Khan Academy "Evaluating Functions" (linked in the Reading).

Priority Problems

If students are running low on time: Problems 1, 5, 7, 9 (one from each part). The Weekly Reflection (Problem 10) is required, worth 5 points. It can be short (3-5 sentences) but students should not skip it.