# How Can They Tell?

### Summary

Students will compare the characteristics of arcade tokens to those of a circulating U.S. quarter to determine how a video game can tell the difference between the two.

• Nickel
• Dime
• Quarter

• Generic

### Objectives

• Students will compare the characteristics of arcade tokens to those of a circulating U.S. quarter.
• Students will determine how a video game can tell the difference between an arcade token and a circulating quarter.

• Science

### Minor/supporting Subject Area Connections

• Language Arts
• Math

### Class Time

Sessions: One
Session Length: 60 minutes
Total Length: 0-45 minutes

• Whole group
• Pairs

### Terms and Concepts

• Characteristics
• Coins
• Comparisons
• Dime
• Game tokens
• Nickel
• Quarter

### Materials

• Quarters
• Nickels
• Dimes
• Balances
• Metric rulers
• Paper
• String
• Data tables

1. Ask your students if they’ve ever been to a video arcade or an amusement park where they needed to put tokens into machines rather than coins. Ask them how they think the machines know that you’re putting in a token rather than money.
2. Divide the students into pairs.
3. Explain to the students that they will be making comparative observations about arcade tokens and currently circulating coins. They will use a balance to measure the mass of the tokens and coins. They will need to record this information on a data table with 5 columns labeled "Type," "Circumference," "Thickness," "Diameter" and "Notes."
4. Have the students wrap a piece of string around the circumference of the arcade token and each of the coins being compared, then measure the string length to determine the circumference of each piece. Have them record this information on the data table as well.
5. Have the students measure the thickness and diameter of the token and the coins using a metric ruler and record this information.

6. Have the students examine the token and write down any unusual characteristics that sets it apart from the coins (such as holes or edges that are flat rather than curved).

7. Have each student pair examine the results of their tests and develop a conclusion as to how machines can tell the difference between tokens and currency, then develop a written statement to support their conclusion. Note that arcade games and vending machines identify coins by their electromagnetic signature. For the purposes of this activity, however, the focus is more on the scientific reasoning than the correctness of the conclusions.

### Enrichments/Extensions

Allow students to compare tokens from different video arcades to see if the conclusion they reached for the first token held true for tokens used in other locations.

Use the collected data and written conclusions as well as visual observation of the group interactions and measuring practices to ascertain whether the students have met the lesson objectives.

There are no related resources for this lesson plan.

Discipline: Math
Domain: 6.SP Statistics and Probability
Cluster: Summarize and describe distributions
Standards:

• 6.SP.4. Display numerical data in plots on a number line, including dot plots, histograms, and box plots.
• 6.SP.5. Summarize numerical data sets in relation to their context, such as by:
• Reporting the number of observations.
• Describing the nature of the attribute under investigation, including how it was measured and its units of measurement.
• Giving quantitative measures of center (median and/or mean) and variability (interquartile range and/or mean absolute deviation), as well as describing any overall pattern and any striking deviations from the overall pattern with reference to the context in which the data were gathered.
• Relating the choice of measures of center and variability to the shape of the data distribution and the context in which the data were gathered.

Discipline: Mathematics
Domain: 6-8 Measurement
Cluster: Apply appropriate techniques, tools, and formulas to determine measurements.
Standards:

In grades 6–8 all students should

• use common benchmarks to select appropriate methods for estimating measurements;
• select and apply techniques and tools to accurately find length, area, volume, and angle measures to appropriate levels of precision;
• develop and use formulas to determine the circumference of circles and the area of triangles, parallelograms, trapezoids, and circles and develop strategies to find the area of more-complex shapes;
• develop strategies to determine the surface area and volume of selected prisms, pyramids, and cylinders;
• solve problems involving scale factors, using ratio and proportion; and
• solve simple problems involving rates and derived measurements for such attributes as velocity and density.

Discipline: Science
Domain: 5-8 Content Standards
Cluster: Physical Science
Standards:

• Properties and changes of properties in matter
• Motions and forces
• Transfer of energy

Discipline: Science
Domain: 5-8 Content Standards
Cluster: Science as Inquiry