Week 1 — Assignment (Adaptive Learning) · Opportunity Cost & the PPF Problem Set

Course: Principles of Microeconomics (ECON 1) · Silver Oak University (fictional sample) · Prof. Kessler
Objective 1 · SLO A & B · Assignment 1 of 14 · 100 points
This is the configured (adaptive) variant. An AI coach gives you the problems one at a time, grades each against an embedded rubric, lets you retry a fresh version, and produces a self-scored report. You submit the report (first line STUDENT'S SCORE: X/100) + your chat share link. (The traditional, instructor-graded version is in I-assignment-and-rubric-week-01-traditional.md.)

How to run this

1. Open an approved chatbot (Gemini, Claude, ChatGPT). Copy the whole gray box and paste it as one message.
2. Solve each problem; the coach grades it, teaches the gaps, and offers a fresh variant to raise your score.
3. When you get the report, submit it (it starts with STUDENT'S SCORE: X/100) plus your chat share link in Canvas. Due Sun, Sep 6.

You are my assignment coach and grader for Week 1 of Principles of Microeconomics (ECON 1)
at Silver Oak University. Give me the problems below ONE AT A TIME, let me solve each, grade
my answer against the rubric, show me how to improve, and let me re-try a fresh version to
raise my score. Grade ONLY against the answer key and rubric below — never invent problems,
answers, or scores. Redo any arithmetic yourself and SHOW YOUR WORK before telling me I'm
wrong. Score honestly; a wrong answer scores low, a strong answer earns full marks.

START: greet me in 1–2 sentences, ask my FIRST NAME, then give Problem 1 exactly as written.
If I answer without giving my name, keep going but ask before the final report. ONE problem
at a time; never show the whole set, the answers, the variants, or the rubric. After each
answer: grade it, say what I did well, TEACH the gap, then offer a re-attempt on the FRESH
VARIANT (update my score to my BEST attempt, capped at full marks). Judge meaning, not
wording. Every message ends with a problem, a question, or a next step.

================= PROBLEM 1 (25 pts) — Opportunity cost in dollars =================
PROBLEM: "You have 5 free hours on Saturday. You could work at a job that pays $16/hour, or
study for free. In dollars, what is the opportunity cost of spending all 5 hours studying?
Show the calculation and say what the number means."
VETTED ANSWER: 5 hours × $16 = $80. The opportunity cost of studying = $80 of forgone wages
(income given up). Interpretation matters: it's not a fee paid, it's pay not earned.
RUBRIC: 25 = correct $80 WITH the calculation AND an interpretation in words. 15–20 = right
number, weak/again missing interpretation. 8–14 = method right, arithmetic slip. 0–7 = treats
cost as $0/"free," or uses the wrong idea (e.g., a price tag).
FRESH VARIANT: "Same setup, but 6 hours at $14/hour. Opportunity cost of studying all 6
hours?" ANSWER: 6 × $14 = $84 of forgone wages (same rubric).

================= PROBLEM 2 (25 pts) — Reading a PPF =================
PROBLEM: "A small shop has a straight-line PPF: it can make 30 phone screens (and 0 cases) or
60 cases (and 0 screens). (a) What is the opportunity cost of producing 1 phone screen, in
cases? (b) Is the combination 20 screens AND 15 cases efficient, inefficient, or
unattainable? Briefly justify (the frontier is 2·screens + cases = 60)."
VETTED ANSWER: (a) 60 cases ÷ 30 screens = 2 cases per screen. (b) Check 2·20 + 15 = 55,
which is LESS than 60, so resources are left idle → INEFFICIENT (inside the frontier).
RUBRIC: 25 = both parts correct with reasoning. 15–20 = one part fully right, other partly.
8–14 = right method, one error (e.g., flips the ratio to ½ a case, or calls 55 'unattainable').
0–7 = both wrong.
FRESH VARIANT: "A workshop can make 40 tables (and 0 chairs) or 20 chairs (and 0 tables),
straight-line (tables + 2·chairs = 40). (a) Opportunity cost of 1 chair, in tables? (b) Is 10
tables AND 12 chairs efficient, inefficient, or unattainable?" ANSWER: (a) 40 ÷ 20 = 2 tables
per chair. (b) 10 + 2·12 = 34 < 40 → INEFFICIENT.

================= PROBLEM 3 (25 pts) — Comparative statics: a shifting PPF =================
PROBLEM: "A bakery's PPF is for BREAD (x-axis) and CAKES (y-axis). The bakery buys a new oven
that DOUBLES its bread output but does nothing for cakes. Describe exactly how the PPF
changes — which intercept moves, which way, and does the whole curve shift or just pivot?"
VETTED ANSWER: The BREAD (x) intercept moves OUTWARD (to the right) — more max bread. The CAKE
(y) intercept is UNCHANGED. So the PPF PIVOTS outward along the bread axis only (it does not
shift out uniformly). Intermediate points (making both goods) gain some bread capacity too.
RUBRIC: 25 = correct direction (outward), correct axis (bread only), and identifies it as a
PIVOT not a parallel shift. 15–20 = outward + bread axis, but calls it a uniform shift. 8–14 =
right idea, wrong axis or vague. 0–7 = shifts inward or wrong good.
FRESH VARIANT: "Instead, a flood destroys half the bakery's ovens (used for BOTH goods).
Describe the PPF change." ANSWER: the WHOLE PPF shifts INWARD (both intercepts fall) — less of
both goods; a uniform inward shift (economic contraction).

================= PROBLEM 4 (25 pts) — Positive vs. normative + reasoning =================
PROBLEM: "Label each claim POSITIVE or NORMATIVE, then in 3–4 sentences argue whether a city
'should' build a new stadium, keeping the positive and normative parts separate: (a) 'A new
stadium would create about 1,200 construction jobs.' (b) 'The city ought to prioritize parks
over stadiums.' (c) 'Stadium subsidies rarely pay for themselves in tax revenue.' (d)
'Taxpayer money shouldn't fund private teams.'"
VETTED ANSWER: (a) POSITIVE (testable jobs prediction). (b) NORMATIVE ('ought'). (c) POSITIVE
(an empirical claim about tax revenue). (d) NORMATIVE ('shouldn't' — a value judgment). The
short argument earns credit for (i) correct labels and (ii) a take that keeps the *facts*
(jobs, tax revenue) distinct from the *values* (what the city should prioritize) — either
side is acceptable if reasoned and fair.
RUBRIC: 25 = all four labels correct + a reasoned paragraph that visibly separates positive
from normative. 15–20 = 3 labels right and/or the paragraph blends the two a little. 8–14 = 2
labels right or no real separation. 0–7 = mostly mislabeled.
FRESH VARIANT: "Label and argue the same way for a proposed soda tax: (a) 'A soda tax would
cut sugary-drink sales by ~10%.' (b) 'The government should discourage unhealthy diets.' (c)
'The tax falls hardest on low-income households.' (d) 'It's unfair to tax people's food
choices.'" ANSWER: (a) POSITIVE, (b) NORMATIVE, (c) POSITIVE, (d) NORMATIVE.

================= COMPLETION =================
After all four problems (and any re-attempts), produce EXACTLY:
    STUDENT'S SCORE: X/100
    WEEK 1 ASSIGNMENT — Opportunity Cost & the PPF
    Student: [name] | Date: ___
    Problem 1: a/25 — [one-line note]
    Problem 2: b/25 — [one-line note]
    Problem 3: c/25 — [one-line note]
    Problem 4: d/25 — [one-line note]
    Strongest skill: ___
    Worth another look: ___
Then say, verbatim: "Copy this entire report AND your share link to this chat, and submit both
in Canvas for this assignment." End with one genuine sentence of encouragement.

Instructor grading note + rubric (for Canvas)

Record the AI score (line 1); spot-check a sample against the chat share link. The embedded key makes scores consistent across chatbots. Summary rubric (each problem to 25, total 100):

Quality gate (self-checked): every number pre-computed/verified — P1 5×16=80 and variant 6×14=84; P2 60÷30=2 cases, 2·20+15=55<60 inefficient (variant 40÷20=2, 10+24=34<40); every curve-shift direction checked — P3 new oven → outward PIVOT on the bread axis only; flood → uniform inward shift. No free-text item is auto-graded against a single "right" wording (P4 grades labels + reasoned separation).

Canvas placement block

canvas_object    = Assignment
title            = "Week 1 Assignment — Opportunity Cost & the PPF (adaptive)"
assignment_group = "Assignments"
points_possible  = 100
grading_type     = points
submission_types = [online_text_entry, online_url]
due_offset_days  = 6
published        = true
submission_note  = "Paste the AI summary report (score on line 1) + the chat share link."
provenance       = "~ Prof. Kessler's edition · Fall 2026 · built with thecoursemaker.com"

Traditional variant — for comparison. This course is configured adaptive learning, so the actual Week-1 assignment is the AI-coached version in I-assignment-and-rubric-week-01.md. This file shows the same problem set built the traditional way — students complete it and submit; the instructor grades against the rubric. (Choosing assignment_type = traditional at setup generates this style.)

Course: Principles of Microeconomics (ECON 1) · Silver Oak University (fictional sample) · Prof. Kessler
Objective 1 · SLO A & B · Assignment 1 of 14 · 100 points · Due Sun, Sep 6

The Assignment

Show your work and write your interpretations in complete sentences. Submit as a document or text entry.

Problem 1 — Opportunity cost in dollars (25 pts). You have 5 free hours on Saturday. You could work at a job paying $16/hour, or study for free. In dollars, what is the opportunity cost of spending all 5 hours studying? Show the calculation and explain in words what the number means.

Problem 2 — Reading a PPF (25 pts). A small shop has a straight-line PPF: 30 phone screens (and 0 cases) or 60 cases (and 0 screens); the frontier is 2·screens + cases = 60.
(a) What is the opportunity cost of 1 phone screen, in cases?
(b) Is the combination 20 screens and 15 cases efficient, inefficient, or unattainable? Justify with the equation.

Problem 3 — A shifting PPF (25 pts). A bakery's PPF is for bread (x-axis) and cakes (y-axis). It buys a new oven that doubles bread output but does nothing for cakes. Describe exactly how the PPF changes — which intercept moves, which direction, and whether the whole curve shifts or just pivots.

Problem 4 — Positive vs. normative + reasoning (25 pts). Label each claim positive or normative, then in 3–4 sentences argue whether a city should build a new stadium, keeping the positive and normative parts separate:
(a) "A new stadium would create about 1,200 construction jobs." (b) "The city ought to prioritize parks over stadiums." (c) "Stadium subsidies rarely pay for themselves in tax revenue." (d) "Taxpayer money shouldn't fund private teams."

AI note. This is the traditional format — submit your own work. You may use an approved chatbot to check a definition, but add a one-line note of which tool and how. (In the adaptive version, working the problems with the chatbot is the activity.)

Grading rubric — 100 points

Instructor answer key & worked solutions — REMOVE BEFORE PUBLISHING TO STUDENTS

• P1: 5 × $16 = $80 of forgone wages. It's income not earned, not a fee paid — the real cost of "free" study time. (Numbers pre-computed/verified.)
• P2: (a) 60 ÷ 30 = 2 cases per screen (state in the other good; the inverse, ½ screen per case, is the common flip). (b) 2·20 + 15 = 55 < 60, so 5 "units" of capacity sit idle → inefficient (inside the frontier). (Verified.)
• P3: New oven doubles bread only → the bread (x) intercept moves outward, the cake (y) intercept is unchanged → the frontier pivots outward along the bread axis (NOT a uniform parallel shift). Classic error: saying the whole curve shifts out evenly. (Curve-shift direction verified.)
• P4: (a) positive (testable jobs figure), (b) normative ("ought"), (c) positive (empirical tax-revenue claim), (d) normative ("shouldn't"). Full credit on the paragraph requires keeping the facts (jobs, revenue) distinct from the values (priorities); either verdict is fine if reasoned and fair (evenhandedness).

Quality gate (self-checked): all numbers re-computed in Python ($80; 60÷30=2 and 55<60; variant checks); every curve-shift direction verified (bread-axis outward pivot; inward contraction). Distractors/traps named: flipped opportunity-cost ratio, "inefficient vs. unattainable," uniform-shift vs. pivot, "positive = good."

Canvas placement block

canvas_object    = Assignment
title            = "Week 1 Assignment — Opportunity Cost & the PPF (traditional)"
assignment_group = "Assignments"
points_possible  = 100
grading_type     = points
submission_types = [online_upload, online_text_entry]
due_offset_days  = 6
rubric_ref       = "w01-assignment-rubric"
published        = true
provenance       = "~ Prof. Kessler's edition · Fall 2026 · built with thecoursemaker.com"