Use a table to make an economic decision, find the opportunity cost and compare uses of resources

Learning goal: Use a table that organizes data to identify relationships and demonstrate a rate of change, and use it to make an economic decision; explain that individuals make decisions due to the scarcity of resources and that every economic decision involves trade-offs and opportunity cost; and explain that resources can be used in various ways to produce goods and services. This lesson teaches three statements from Ohio's July 2026 K–8 social studies standards, which the Ohio Department of Education and Workforce anticipates districts will begin to implement in the 2027-28 school year.

Resources and scarcity. Resources are the things people use to produce goods and services. They include natural resources (land, water, trees), human resources (people's work and skills), and capital resources (tools, machines and buildings). Time is also a resource. Scarcity means there are not enough resources to make everything people want. Because resources are scarce, individuals have to make decisions about how to use them.

Resources can be used in various ways. The same resource can produce different goods and services. A sheet of cardstock can become a bookmark or a greeting card. A piece of land can become a farm field, a park or a parking lot. A person's hour of work can be spent baking bread or tutoring a student. Some uses compete for the same resource: the part of a field planted in corn cannot also be a parking lot. Other uses can share a resource, such as a pumpkin patch that is also a place for school field trips. When two uses compete, choosing one means giving up the other. A resource can sometimes be split, such as half a field in corn and half in pumpkins, but then each use gets less. Either way, choosing how to use it is an economic decision.

Trade-offs and opportunity cost. A trade-off is giving up one thing to get another. Opportunity cost is the value of the next-best alternative you give up when you make a decision. It is not everything you gave up, only the one choice you would have picked second. If you choose to spend Saturday morning at soccer practice, and your next-best choice was going to the library, the opportunity cost of soccer is the library visit.

The misconception. Many students think opportunity cost is the money something costs. Money price is part of the story, but opportunity cost is what else you could have done with the resource. Even something free has an opportunity cost if it uses your time. Another mistake is to count every possible choice as the opportunity cost. It is only the next-best one.

How tables help. A table organizes data in rows and columns. Each column has a heading that tells what the numbers mean. When data are organized, it is easier to identify relationships, such as "the more hours we work, the more bookmarks we make." A table can also demonstrate a rate of change: how much one quantity changes each time another quantity goes up by one.

A fully worked model (hypothetical). A third-grade class runs a small craft sale to raise money for the school garden. It has 3 hours of work time on one afternoon (a scarce resource). It can use the time to make bookmarks or greeting cards. The class tests its speed and makes this table:

Relationship: In both columns, more hours means more items. Rate of change: bookmarks go up by 10 each hour (10 → 20 → 30), so the rate of change is 10 bookmarks per hour. Cards go up by 4 each hour (4 → 8 → 12), so the rate is 4 cards per hour.

Now add prices. The class plans to sell bookmarks for $1 each and cards for $3 each. The paper and markers are donated, so both choices cost the class the same (nothing) for materials, and the money from sales all goes to the garden. Money per hour: bookmarks 10 × $1 = $10 per hour; cards 4 × $3 = $12 per hour. For all 3 hours: bookmarks earn 30 × $1 = $30; cards earn 12 × $3 = $36.

Decision: If the goal is to raise the most money, the materials cost the same for both, and the class expects to sell everything, it should make cards ($36 in sales is more than $30). Opportunity cost: the next-best alternative is making bookmarks, so the opportunity cost of making cards is the 30 bookmarks, worth $30, the class did not make. Trade-off: the class gives up bookmarks to get cards. Notice that the same resource, 3 hours of work, could produce two different goods; that is resources being used in various ways.

Conditions matter. This decision depends on assumptions: that every item sells and that the materials for cards cost no more than the materials for bookmarks. If the class learns that only 6 people want cards, then it could sell only 6 × $3 = $18 of cards, and bookmarks might be better. A good economic decision states the conditions it depends on.

Worked example 1: Finding a rate of change. A hypothetical bakery table shows: 1 hour → 12 muffins, 2 hours → 24 muffins, 3 hours → 36 muffins. Subtract each row from the next: 24 − 12 = 12 and 36 − 24 = 12. The rate of change is 12 muffins per hour. The relationship: every added hour adds 12 muffins.

Worked example 2: Opportunity cost of time. Maya has one free hour. Her choices, in order of what she wants most: (1) help her grandfather in his garden, (2) play a board game, (3) watch a show. She chooses the garden. Her opportunity cost is the board game, her next-best alternative. It is not the show, because the show was only her third choice.

Worked example 3: One resource, various uses. A hypothetical farmer has one field. Planted in corn, it produces a crop to sell. Used as a pumpkin patch with hayrides, it provides a service to visitors as well as a good. The farmer compares expected earnings: corn $900, pumpkin patch $1,200 (both hypothetical). If the farmer chooses the pumpkin patch, the opportunity cost is the corn crop worth $900. The field can be used in various ways to produce goods and services. Corn and a pumpkin patch compete for the same ground, so in this example the farmer uses the whole field one way.

Representation task: Copy the craft-sale table and add a fourth row for 4 hours, continuing each rate of change. (Check: 40 bookmarks and 16 cards.) Under the table, write one relationship you see and the rate of change for each column.

Independent performance: Create your own table for a hypothetical decision: a scarce resource (time, money or materials), two ways to use it, and at least three rows of data. Use the table to make a decision. Read the success criteria before you start: each one is part of the task.

Success criteria: (1) the table has a title and clear column headings; (2) you state one relationship and one rate of change from the data; (3) you name the scarce resource; (4) you show that the resource could be used in two different ways to produce goods or services; (5) you state your decision, the trade-off and the opportunity cost (the next-best alternative); (6) you name one condition that could change your decision.