Gains on One Side, Costs on the Other
A 45-minute Grade 3 lesson on weighing what a choice gains against what it costs the person making it.
Gains on One Side, Costs on the Other is a free 45-minute Grade 3 to Grade 5 social studies lesson plan for Common Core standard D2.Eco.1.3-5 — weigh up what a choice gains against what it costs. It is timed across 5 sections, gives the exact wording to use where the wording carries the mathematics, names 3 misconceptions with the teaching move that addresses each, and ends with an exit ticket and a printable worksheet with its answer key.
- Grade:
- Grade 3 to Grade 5
- Length:
- 45 minutes
- Standard:
- D2.Eco.1.3-5
Grade 3 to Grade 5 · Economics
D2.Eco.1.3-5
Compare the benefits and costs of individual choices.
Objective
Students will be able to name both the benefit and the cost of one economic choice.
Students are successful when they can
- Names the benefit of a choice.
- Names the cost, including what was given up.
- Says which side is larger and why.
What you need
- The railway timetable, with both fares
- A two-column balance sheet
- The printable practice sheet linked at the end of this plan
The lesson
Warm-up — six pence or two shillings
5 min- Read both fares from the timetable and ask which anybody would choose.
- Then read that third class is open to the weather.
Teach — fill both columns
15 min- Take the farmer sending milk by train. Benefit: it reaches town fresh in an hour.
- Cost: the fare, every single day.
- Add the hidden cost: the cart and horse he no longer uses but still keeps.
- Do the boatman retraining as a porter. Benefit: work that exists. Cost: weeks earning nothing.
- Say the rule: a cost is not only money paid, it is what you gave up to choose this.
- Ask which side is larger for the farmer, and insist on a reason.
“What did they have to give up in order to choose this?”
Guided practice — four choices
13 min- Pairs fill both columns for four choices from the valley.
- For two, they add what was given up rather than paid.
- Pairs compare and argue one 'which side is larger'.
Independent practice
9 min- Students complete the 'What It Gains, What It Costs' page.
- Check that costs include what was given up.
Close
3 min- Take one choice the class made this week and name both columns.
What goes wrong, and why
Each of these is a reasoning error rather than carelessness. The fix addresses the reasoning.
Counts only money as a cost.
Why: Money is the visible payment.
Fix: Ask what else was given up. Time, safety and the option not taken are all costs.
Says a choice with any cost is a bad choice.
Why: Cost sounds like a warning.
Fix: Every choice has a cost. The question is whether the gain is larger.
Fills only the column that matches their opinion.
Why: The other column argues against them.
Fix: Require both. An unfilled column is an unfinished answer.
If they are not there yet
- Two choices with the benefit already written.
- Offer three costs and ask which belongs.
If they finish early
- Find a choice whose cost fell on somebody else.
- Say how the balance changes if the fare doubles.
- Name a cost that only appears years later.
Exit ticket
A boatman retrains as a railway porter. Name one benefit and one cost.
What to look for: Work that exists, against weeks earning nothing while learning. Only a benefit means the cost column needs another run.
Printable practice for D2.Eco.1.3-5
Free to print and copy, answer key included. Each sheet can generate a fresh set of problems for a retake.
- What It Gains, What It CostsCircle the best answer.
Questions about Gains on One Side, Costs on the Other
How long does the Gains on One Side, Costs on the Other lesson take?
45 minutes, split across 5 timed sections: warm-up 5 min, teach 15 min, guided practice 13 min, independent practice 9 min, close 3 min. The minutes are stated per section and add up to the stated length, so the plan can be cut or extended at a section boundary rather than abandoned halfway.
Which standard does Gains on One Side, Costs on the Other teach?
D2.Eco.1.3-5 — D2.Eco.1.3-5, Economics for Grade 3 to Grade 5: “Compare the benefits and costs of individual choices.” In plain terms, weigh up what a choice gains against what it costs.
What do I need to teach this lesson?
The railway timetable, with both fares, a two-column balance sheet and the printable practice sheet linked at the end of this plan. Everything listed is either ordinary classroom equipment or a free printable from this site — there is nothing to buy and nothing to prepare beyond photocopying.
What mistakes should I expect in this lesson?
Three, each a reasoning error rather than carelessness: counts only money as a cost; says a choice with any cost is a bad choice and fills only the column that matches their opinion. The plan gives the thinking behind each one and the teaching move that addresses the thinking rather than the symptom.
How do I know whether the lesson worked?
The exit ticket asks: “A boatman retrains as a railway porter. Name one benefit and one cost.” Work that exists, against weeks earning nothing while learning. Only a benefit means the cost column needs another run. That tells you whether the class needs a reteach or a thirty-second conversation before you plan tomorrow.
Is there a worksheet to go with Gains on One Side, Costs on the Other?
Yes — 1 printable D2.Eco.1.3-5 worksheet, linked at the end of the plan and free like the rest of the site. Each one comes with an answer key and 25 versions, so the practice after the lesson can be a different paper on every desk.
Is Gains on One Side, Costs on the Other free to use?
Yes. The plan, its printables and their answer keys are free to read, print and photocopy for your own class, with no account and no email capture. It was last reviewed on 7 September 2026. Please do not resell it or republish it as your own.
Last reviewed 2026-09-07. Aligned to D2.Eco.1.3-5 of the C3 Framework for Social Studies State Standards.