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Demand Curve Explorer

Run the Demand Curve Explorer MicroSim Fullscreen
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About This MicroSim

This MicroSim demonstrates the law of demand using a coffee shop example. Students adjust a price slider and watch a red point move along a downward-sloping demand curve, showing the inverse relationship between price and quantity demanded. An info box displays the current price and quantity values and provides plain-language commentary about whether demand is high or low at each price level. Scenario buttons let students quickly jump to specific price points to compare outcomes.

How to Use

  1. Drag the Price slider at the bottom of the simulation to change the coffee price from $1 to $10. Watch the red point move along the demand curve and the quantity demanded update in the info box.
  2. Observe the dotted guide lines that connect the point to the axes, making it easy to read the exact price and quantity values.
  3. Click the scenario buttons ("Coffee at $2," "Coffee at $5," "Coffee at $8") at the bottom of the graph to jump to preset price levels and see how dramatically quantity changes.
  4. Read the info box in the upper right to see a description of the demand level at the current price.

Iframe Embed Code

You can add this MicroSim to any web page by adding this to your HTML:

<iframe src="https://dmccreary.github.io/economics-course/sims/demand-curve-explorer/main.html"
        height="452px"
        width="100%"
        scrolling="no"></iframe>

Lesson Plan

Grade Level

9-12 (High School Economics)

Duration

10-15 minutes

Prerequisites

  • Ability to read a basic x-y graph with labeled axes
  • Understanding that consumers make purchasing decisions based on price

Activities

  1. Exploration (5 min): Slowly drag the price slider from $1 to $10 and record the quantity demanded at $2, $5, and $8. Create a simple demand schedule (table) from your observations and verify that it matches the law of demand.
  2. Guided Practice (5 min): Use the scenario buttons to compare coffee at $2 versus $8. Calculate the change in quantity demanded and discuss with a partner why the demand curve slopes downward. Consider what real-world factors explain why people buy more coffee when it is cheaper.
  3. Assessment (5 min): Without looking at the simulation, predict the approximate quantity demanded at $4 and $7. Then check your predictions by setting those prices on the slider. Write a sentence explaining the law of demand in your own words.

Assessment

  • Students can state the law of demand (as price increases, quantity demanded decreases, all else equal)
  • Students can read price and quantity values from the demand curve graph
  • Students can explain why the demand curve slopes downward using real-world reasoning

References

  1. Demand Curve - Wikipedia - Explanation of the demand curve, its slope, and the distinction between movement along the curve and shifts of the curve.
  2. Law of Demand - Investopedia - Overview of the law of demand with practical examples and exceptions.
  3. Law of Demand - Khan Academy - Lesson on demand, demand schedules, and demand curves.