# Practice exam with an answer key that explains each mistake

> Writes a realistic practice exam from your course material, with distractors based on real student mistakes and an answer key that explains each one.

- **Author:** [Mateo Gonzalez (@mateo_gonzalez)](https://promptabide.com/mateo_gonzalez)
- **Tested on:** Claude · Opus 5.5
- **You fill in:** `topic`, `course_level`, `material`, `num_questions`
- **Published:** 2026-08-26
- **Updated:** 2026-09-24
- **Tags:** `study`, `education`, `learning`, `teaching`
- **Keywords:** practice exam generator prompt, make a practice test from my notes, supply and demand practice questions, multiple choice questions with explanations, exam prep prompt with answer key
- **Views:** 631
- **Likes:** 30

**Best for:** Students a week or two before a test who have finished reading and need retrieval practice that shows exactly which misconception they hold.

## Prompt

```
Write a practice exam on {{topic}} for {{course_level}}. It should feel like the real thing and teach me from my mistakes.

Source material (don't test anything outside it):
{{material}}

Exam spec:
- {{num_questions}} questions, mixed: roughly half recall and half application (new scenarios, not examples copied from the material). At least one question combines two ideas.
- Label each question with its type and difficulty (easy / medium / hard).
- Multiple-choice distractors must be mistakes students really make, not obviously silly options.

Then, after a clear "ANSWER KEY" divider:
- The correct answer with a 1-2 sentence explanation.
- For each wrong option or typical wrong answer: the misconception behind it.
- A short "if you got this wrong, review..." pointer to the part of the material.

Finish with a scoring guide: what score means I'm ready, and which questions to redo if I'm not.
```

## Variables

- `{{topic}}` — The topic the exam covers. (e.g. supply and demand: shifts, equilibrium, price ceilings)
- `{{course_level}}` — The course and level. (e.g. intro microeconomics, first-year college)
- `{{material}}` — Your notes or textbook summary. The exam sticks to this. (e.g. A demand curve shows quantity demanded at each price...)
- `{{num_questions}}` — How many questions. 5-10 keeps the answer key useful. (e.g. 5)

## Example input

```
topic: supply and demand: shifts vs. movements, equilibrium, price ceilings
course_level: intro microeconomics, first-year college
num_questions: 5
material: A demand curve shows the quantity demanded at each price, holding other factors constant. A change in the good's own price causes a movement along the curve (a change in quantity demanded). A change in other factors (income, prices of related goods such as substitutes and complements, tastes, expectations, number of buyers) shifts the whole curve (a change in demand). For normal goods, demand rises with income; for inferior goods, demand falls as income rises. Supply works the same way: the good's own price causes a movement along the curve; input costs, technology, number of sellers and expectations shift it. Equilibrium is where quantity demanded equals quantity supplied. If the price is above equilibrium there is a surplus; below it, a shortage. A price ceiling is a legal maximum price. It is binding only if set below the equilibrium price, where it causes a shortage. A ceiling set above equilibrium has no effect.
```

## Output

*Produced by Claude · Opus 5.5.*

```
**1.** (Recall, easy) The price of coffee rises and people buy fewer cups. This is:
A) a decrease in demand  B) a decrease in quantity demanded  C) a decrease in supply  D) a leftward shift of the demand curve

**2.** (Application, medium) Tea and coffee are substitutes. A frost destroys much of the tea crop. What happens in the coffee market?
A) Demand for coffee shifts right  B) Supply of coffee shifts left  C) Movement along coffee's demand curve  D) Demand for coffee shifts left

**3.** (Application, medium) A city sets a maximum rent of $1,800 for one-bedroom apartments. The equilibrium rent is $1,500. What happens? (short answer)

**4.** (Application, hard, combines two ideas) Instant noodles are an inferior good. A recession cuts incomes, and at the same time a new factory lowers production costs. What happens to the equilibrium quantity and price of instant noodles? (short answer)

**5.** (Application, medium) At $15, 200 concert T-shirts are demanded and 350 are supplied. Name the situation and say which way the price will tend to move. (short answer)

---
**ANSWER KEY**

**1. B.** The good's own price changed, so it's a movement along the curve.
- A and D: the classic mix-up of "demand" (the curve) with "quantity demanded" (a point on it).
- C: blames sellers for a buyer's response.
- *Review:* movements vs. shifts.

**2. A.** The price of a substitute (tea) rises, so more people want coffee at every price.
- B: the frost hit tea, not coffee.
- C: coffee's own price didn't cause this, so it isn't a movement.
- D: gets the direction of substitution backwards.
- *Review:* related goods.

**3. Nothing changes.** A ceiling above equilibrium isn't binding, and rent stays at $1,500.
- Typical wrong answer: "a shortage." That's true only for ceilings set below equilibrium.
- *Review:* price ceilings.

**4. Quantity rises; the price change is unclear.** Lower income raises demand for an inferior good (shift right), and lower costs raise supply (shift right). Both push quantity up, but they push price in opposite directions.
- Typical wrong answers: "demand falls" (treating noodles as a normal good), or naming a definite price change.
- *Review:* normal vs. inferior goods; supply shifters.

**5. A surplus of 150, and the price tends to fall.** Quantity supplied exceeds quantity demanded.
- Typical wrong answer: "shortage," comparing the numbers the wrong way round.
- *Review:* equilibrium.

**Scoring guide**
- 5/5: ready. 4/5: ready, but redo the one you missed tomorrow without notes.
- 3 or fewer: missed 1 or 2? Drill movements vs. shifts. Missed 3 or 4? Re-read price ceilings and inferior goods. Then retake the exam in two days.
```

## Why it works

**"Distractors must be mistakes students really make"** is what separates this from a generic quiz: when you pick a wrong option, the answer key can name the exact misconception you hold, like mixing up "demand" and "quantity demanded."

**"Don't test anything outside it"** keeps the exam aligned with your course rather than the model's idea of the subject. The **half recall, half application** split and the **combined-ideas question** mirror how real exams separate students who memorized from those who understood. **Review pointers and a scoring guide** turn the result into a study plan.

## When not to use it

The model doesn't know your professor's exam style or weighting, so past papers are still the best practice when you can get them. For math-heavy subjects, check the answer key yourself, since calculation errors do slip through. If your material is only a few lines, the questions will repeat each other.

---

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