Dust Bowl Farm: teacher answer key
Public sample teacher key. Includes model answers; open the student worksheet when assigning the activity.
11.7.c: For many Americans, the 1920s was a time of prosperity. However, underlying economic problems, reflected in the stock market crash of 1929, led to the Great Depression. President Franklin D. Roosevelt’s responses to the Great Depression increased the role of the federal government.
Using the worksheet
- Worksheet opens the questions. New questions follow each run; misses add a reflection prompt.
- Recorded automatically: the topsoil prediction, acres plowed and programs used each turn, topsoil and cash at the end, and pass or miss.
- My work offers Copy my work and Turn in a PDF. Nothing is submitted automatically. Review written reasoning separately from game success; blank responses remain visible.
- On shared devices, use Clear my work and tap again to confirm. The game's Start over does not clear worksheet answers. If browser storage is blocked, export before leaving.
Numbers like "#4" match the printed worksheet. Questions marked "After a miss" appear in the game only after a missed run; on paper they are combined into one question near the end.
Level 1: The Great Plow-Up
- To pass: don't buy a tractor in 1910, and plow wheat in the 1915 turn, the 1920 turn, or both, so there is $4,000 at the end of 1924. More acres earn more, most of all at the 1917 to 1919 prices. A tractor bought in 1915 or 1920 works if you plow with it.
- Misses: any tractor bought in 1910 forecloses in 1912 (1911 with 0 acres plowed). 0 acres in both the 1915 and 1920 turns can't pay the mortgage (160 acres in 1910, then 0 and 0, ends 1924 with $2,104). Buying a tractor and then plowing 0 or 80 acres can also fail.
- Topsoil at the end of 1914, by acres plowed in 1910: 0 → 99.8%, 80 → 97.8%, 160 → 95.8%, 240 → 93.8%, 320 → 91.8%. It does not change from 1915 to 1924 (no dry years), so all three turns show the same number.
- Cash left at the end of 1924, after paying the mortgage: 160 acres every turn → $15,016. 320, then 640 with a tractor in 1915, then 640 → $58,711. A passing debrief shows both.
#1. Record what happened: did you keep the farm? Give your topsoil and cash at the end, or the year the bank took the farm. 11.7.c
Example (passed): "We paid off the mortgage. Topsoil 95.8%, $15,016 left at the end of 1924." Example (missed): "We bought a tractor in 1910 and the bank foreclosed in 1912." Check it against the run log on the My work page.
#2. Wheat sold for more than $2 a bushel in 1917 to 1919. Why did plowing more land pay off then? Use the price and the $6 cost of a plowed acre. 11.7.c
In 1919 an acre grew about 14 bushels and wheat sold for $2.16, so it earned about $30 (14 × $2.16 = $30.24). That is far more than the $6 it cost to plow, plus the $1 the grass would have earned, so every extra plowed acre added over $20 that year. World War I demand pushed the price up, so farmers plowed up the grassland, often with tractors bought on credit.
| Common wrong answer | What it shows |
|---|---|
| "Because there was more rain." | Rain helped, but the jump came from the price: the same 12 to 14 bushels sold for more than twice as much. |
| "Because the tractor grew more wheat." | A tractor only lets you plow more than 320 acres. It does not raise the yield of an acre. |
#3. Your topsoil did not drop from 1915 to 1924, no matter how much you plowed. Why not? What would happen to that plowed land in a drought? 11.7.c
Those years had only normal and wet rain, and in the game soil only blows away in dry years. The plowed land was still bare soil with no grass roots. When the 1930s droughts came, it blew away (in Level 2 a fence-to-fence farm falls to 12.8% topsoil while an all-grass farm keeps 82.2%). The good years hid the risk, so plowing in good times set up the disaster.
| Common wrong answer | What it shows |
|---|---|
| "Plowing doesn't hurt the soil." | Doesn't see that the damage waits for a drought. |
| "Wheat holds the soil like grass does." | In dry years plowed land loses soil like bare land. Only grass protects it. |
After a miss: One of your runs did not pass. What went wrong? Use numbers from the debrief. 11.7.c
Tractor in 1910: "We bought a tractor on credit in 1910. In the dry years 1911 and 1912 wheat sold for under $1, so an acre earned about $4 but cost $6, and the $300 tractor payment came due anyway. Cash fell below $0 and the bank foreclosed in 1912." No wheat after 1914: "We plowed 0 acres from 1915 to 1924, so we missed the high war prices and had only $2,104 at the end of 1924, not the $4,000 for the mortgage."
Level 2: The Bust
- To pass: cut to 80, 160, or 240 acres in 1925 (the rain is normal, so grass grows back), then plow 0 acres in 1930. Plowing 80 in 1930 also passes after 160 or 240 (after 160 it ends with only $10). No new tractor is needed. The acreage program isn't required, but it pays $3 × 480 base acres = $1,440 a year in 1933 and 1934 to a farm that plows 0 in 1930.
- Topsoil at the end of 1934 for those plans depends on the 1925 acres, because land taken out in 1930 sits bare through the drought: 80 → 73.5%, 160 → 64.9%, 240 → 56.2%, 320 → 47.5% (miss), 480 → 30.2% (miss). At the end of 1929: 80 → 83.7%, 160 → 82.7%, 240 → 81.7%, 480 → 78.7% (1928 is dry).
- Typical misses: 480 acres both turns has $9,776 at the end of 1929, then the bank forecloses in 1932. 480, then 0, keeps the farm but ends at 30.2% topsoil. 0 acres in 1925 forecloses in 1930 (grass earns $640 a year against $900 in costs). Small farms that keep plowing also run out of cash: 80, then 80 again, forecloses in 1932.
- The debrief's "Same drought, two farms": the grass farm keeps 82.2% topsoil, the fence-to-fence farm falls to 12.8%.
#4. Record what happened: did you keep the farm? Give your topsoil and cash at the end, or the year the bank took the farm. 11.7.c
Example (passed): "We kept the farm with 56.2% topsoil and $3,178 at the end of 1934." Example (missed): "We kept 480 acres and the bank foreclosed in 1932." Check it against the run log on the My work page.
#5. Land you stop plowing stays bare until a normal or wet year lets grass grow back. Why did cutting back in 1925 save more topsoil than cutting back in 1930? 11.7.c
1925 was a normal year, so grass grew back right away on the land we stopped plowing in 1925, and it held the soil when the drought hit. Land taken out of wheat in 1930 never got a normal year, so it sat bare from 1930 to 1934 and blew away like plowed land. Example: 240 acres in 1925, then 0, ended at 56.2% topsoil. 480 acres, then 0, ended at 30.2%.
| Common wrong answer | What it shows |
|---|---|
| "It doesn't matter when you cut back." | Misses that grass needs rain to grow back. |
| "Cutting back in 1930 is better, because that's when the drought started." | Thinks stopping plowing protects the soil right away. Bare land blows just like plowed land. |
#6. In 1931 and 1932, wheat sold for only $0.38 a bushel and the crops dried up. Why did more plowed acres mean bigger losses? What did the tractor payments do? 11.7.c
In 1931 an acre grew less than 1 bushel and earned under $0.40, but it still cost $6 to plow, so every plowed acre lost more than $5. More acres meant bigger losses. The $300 tractor payment came due every year through 1932, no matter how bad the harvest was. Debt taken on in good years had to be paid in bad ones. Example: a farm that kept 480 acres had $9,776 at the end of 1929 and was foreclosed in 1932.
| Common wrong answer | What it shows |
|---|---|
| "Low prices hurt every farm the same." | Doesn't connect the $6 cost of each plowed acre to the size of the loss. |
| "The tractor made farming cheaper." | Misses that the loan payment is a fixed cost that stays when income falls. |
After a miss: One of your runs did not pass. What went wrong? Name the year and use numbers from the debrief. 11.7.c
Kept plowing: "We kept 480 acres. From 1930 to 1932 each acre earned under $1 but cost $6, and the tractor payment kept coming, so cash fell below $0 and the bank foreclosed in 1932." Cut back too late: "We stopped plowing in 1930, but no normal year came for grass to grow back, so 480 bare acres blew away and topsoil fell to 30.2%, below 50%." All grass in 1925: "Grass earned only $640 a year, but costs were $900, so the bank foreclosed in 1930."
Level 3: Recovery
- The only winning plan: plow 0 acres, join the acreage program, plant a shelterbelt, and return fields to grass. Contour plowing is optional (it does nothing with 0 acres plowed). A new tractor still passes but adds debt.
- Winning result: 55.6% topsoil and $5,740 cash at the end of 1940. Topsoil by year: 46.8, 48.5, 50.4, 52.2, 53.9, 55.6 (about +1.8 a year). The matching prediction is 55.6%.
- Money: the program pays $3 × 400 acres = $1,200 a year. That covers re-seeding (400 × $2 = $800, once) and the shelterbelt ($200 a year).
- Typical misses: no acreage program → foreclosed in 1935. No shelterbelt → 54.2%, just under. No re-seeding → the 400 bare acres blow away (21.9% even with a shelterbelt). Still plowing 80 acres with the program, shelterbelt, and grass → 49.8% (adding contour plowing's $80 a year forecloses in 1935). Keeping 400 acres → foreclosed in 1935.
#7. Record what happened: did you keep the farm? Give your topsoil and cash at the end, or the year the bank took the farm. 11.7.c
Example (passed): "We kept the farm with 55.6% topsoil and $5,740 at the end of 1940." Example (missed): "Topsoil ended at 54.2%, under the 55% goal." Check it against the run log on the My work page.
#8. Which programs and practices did you use? What did each one do for your farm, and how fast did your topsoil come back? 11.7.c
Winning plan: no plowing, the acreage program, a shelterbelt, and returning fields to grass. The acreage program paid $3 for each of 400 acres held out of wheat ($1,200 a year), and that cash paid for re-seeding ($800) and the shelterbelt ($200 a year). Without it the bank forecloses in 1935. Re-seeding turned the bare fields into grass right away, and grass rebuilt about 2 points of topsoil a year. The shelterbelt cut the neighbors' dust in half. Even with all of it, topsoil came back slowly: from 45% to 55.6% in six years, about 1.8 points a year.
| Common wrong answer | What it shows |
|---|---|
| "Contour plowing saved our soil." | With 0 acres plowed, contour plowing changes nothing. The grass and the shelterbelt did the work. |
| "The New Deal fixed the soil right away." | Misses the slow climb: under 2 points a year, even with every practice. |
#9. Dust from the neighbors' fields blew onto your farm, even onto your grass. Why did fixing the Dust Bowl take the federal government, not just one careful farmer? 11.7.c
Dust storms were shared. The neighbors kept their land plowed, so their soil blew onto every farm (1.4 points of topsoil even with a shelterbelt, 2.8 without). One farmer could not stop that alone. The federal government could reach farmers across the Plains at once: it paid them to plant less wheat (the acreage program, from 1933) and created the Soil Conservation Service (April 27, 1935) to help farmers use practices like contour plowing and grass. These programs made the federal government's role in farming much bigger.
| Common wrong answer | What it shows |
|---|---|
| "One farmer can fix it by planting grass." | Misses the neighbors' dust, which hit even all-grass farms. |
| "The government should have stopped the drought." | Mixes up the drought with the land use that turned it into a disaster. |
After a miss: One of your runs did not pass. What went wrong? Use numbers from the debrief. 11.7.c
No program: "Without the program's $1,200 a year we couldn't pay for re-seeding and the shelterbelt, and the bank foreclosed in 1935." No shelterbelt: "The neighbors' dust took 2.8 points, so we ended at 54.2%, just under 55%." Still plowing: "Our 80 plowed acres lost soil in every dry year and couldn't rebuild topsoil the way grass does, so we ended at 49.8%."
When a run did not pass (#10)
Any of the After a miss answers above. Look for the rule named correctly and the specific thing that went wrong.
Wrap-up: the Dust Bowl and the New Deal
#11. What caused the Dust Bowl, and how did the federal government's role grow in response? Use evidence from at least two levels. 11.7.c
Claim: The Dust Bowl was not caused by drought alone. Farmers plowed up the grassland when wartime prices were high, often with tractors bought on credit. When drought and low prices hit in the 1930s, the bare land blew away and debt sank farms. The New Deal paid farmers to plant less and spread conservation, which made the federal government's role much bigger, but the soil came back slowly. Evidence: In Level 1, an acre earned about $30 at the 1919 price of $2.16, against a $6 cost, and topsoil didn't drop from 1915 to 1924 because those years were wet or normal. In Level 2, in the same drought, the all-grass farm kept 82.2% topsoil and the fence-to-fence farm fell to 12.8%; a farm that kept 480 acres went from $9,776 in 1929 to foreclosure in 1932. In Level 3, the acreage program's $1,200 a year paid for grass and a shelterbelt, and topsoil climbed only from 45% to 55.6% in six years. Reasoning: Drought only blows away bare, plowed land, so the choices farmers made in the good years set up the disaster. Because dust from every farm hit its neighbors, one farmer couldn't fix it, so the federal government acted for everyone: it paid farmers directly and sent experts to change how they farmed.