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Lesson plan Grade 6 Science

Wintershaw's April Snowpack Record: Asking Better Questions

A 55-minute grade 6 lesson where students analyze sixty years of April snowpack depths at Wintershaw and write testable questions about what has changed.

Objectives

  1. Students will describe a sixty-year trend in April snowpack using a change, a percent change, and a mean.
  2. Students will write questions about possible causes of a measured change and sort them by the evidence each needs.
  3. Students will explain why a multi-year record supports stronger claims than a single winter.

Vocabulary

Snowpack
The snow that piles up in the mountains over the winter. As it melts in spring and summer, it acts like a giant water tank feeding rivers and reservoirs.

Also: runoff, trend, evidence, percent decrease

Teacher overview

Mountain snow works as a reservoir that fills in winter and releases through the summer, so a town that depends on snowmelt watches the April measurement closely. This lesson gives students sixty years of April snow depth, one reading per decade, from a fictional ridge above the town of Wintershaw and puts the emphasis on the scientific practice of asking questions rather than on reaching a verdict. The misconception to name for students is that one dry winter proves a long-term change. Students often argue from the most recent year they remember, so the lesson deliberately hands them a record long enough that a single value cannot carry the claim.

Procedure

Hook (5 min): Ask students where the water in a mountain town comes from in August, months after the last snowfall. Take three responses, then show only the 1965 and 2025 rows of the Wintershaw record and ask what a planner would want to know before acting on those two numbers.

Direct instruction (10 min): Explain how snowpack depth on April 1 is measured and why that date is used as the yearly peak. Distinguish a measurement, which the record gives, from an explanation, which the record does not. Model the difference between a question the data can answer, such as how much the depth changed, and a question the data cannot answer alone, such as why the change happened.

Data reading (12 min): Distribute the handout. Pairs complete questions 1 through 4 and check each other's arithmetic. Circulate and push pairs to state what attribute is being measured, not just the number they computed.

Question generation (13 min): Each student writes three questions about possible causes on separate sticky notes. Teams of four sort all twelve notes on chart paper into two columns, one for questions the Wintershaw record alone can answer and one for questions that need other evidence. Teams then choose the single strongest question in the second column and write beneath it the evidence that would be needed.

Independent practice (10 min): Students complete handout question 5 individually, writing one question and naming its evidence.

Closure and formative check (5 min): Collect the sticky-note charts and read three questions aloud, asking the class to signal thumbs up if the question belongs in the column where its team placed it. If fewer than three quarters of the class agrees on a given question, work through that sort with the class before ending.

Wintershaw's April Snowpack Record: Asking Better Questions — Grade 6 Science
Name: ____________________________ Date: ______________

Student Handout

The table gives April 1 snow depth on Wintershaw Ridge, measured once every ten years. The town of Wintershaw gets its summer water from the melt off this ridge.

Year April 1 snow depth (inches)
1965 80
1975 75
1985 70
1995 65
2005 60
2015 50
2025 48
  1. The April 1 depth was 80 inches in 1965 and 48 inches in 2025. How many inches did the depth fall between those two readings?
  2. Using the 1965 depth of 80 inches as the starting amount, what percent decrease does that fall represent?
  3. The seven readings are 80, 75, 70, 65, 60, 50, and 48 inches. What is the mean depth?
  4. Each inch of April 1 snow depth supplies about 6 million gallons of summer runoff to Wintershaw. Using your answer from question 1, how many million gallons less did the 2025 snowpack supply than the 1965 snowpack?
  5. Write one question you would ask about why the Wintershaw record changed. Then name the evidence that would help answer your question.

From Water for Schools (waterforschools.org). This material is in the public domain (CC0) and may be copied, edited, and shared freely.

Answer Key
  1. Answer: 32 inches.
    Subtract the later reading from the earlier one: 80 - 48 = 32 inches.
  2. Answer: 40 percent.
    Divide the fall by the starting depth, so 32 divided by 80 gives 0.4. Multiply by 100 to get 40 percent.
  3. Answer: 64 inches.
    Add the seven readings to get 448, then divide by 7. The mean depth is 64 inches.
  4. Answer: 192 million gallons.
    Multiply the fall in inches by the runoff each inch supplies: 32 x 6 = 192 million gallons.
  5. Answer: Any testable question paired with the evidence it would need.
    Strong responses pair a cause question with a specific record, such as asking whether winter temperatures on the ridge rose and naming a temperature record from the same station, or asking whether total winter precipitation fell and naming a precipitation record. Accept any question about a possible cause when the named evidence could actually settle it. Do not accept a question the snow depth column already answers, such as how much the depth fell.

Differentiation

Support

Provide the seven readings already added, with the sum of 448 given, so question 3 becomes a single division. Give a worked percent decrease example from a different fictional ridge, such as a fall from 50 inches to 40 inches, before students attempt question 2.

Extension

Ask students to find the mean of the first four readings and the mean of the last three, compare those two means, and explain in writing why comparing group means can describe a trend more convincingly than comparing the first and last values alone.

ELL supports

Pre-teach "snowpack," "runoff," and "trend" with a two-panel drawing of a snow-covered ridge in April and the same ridge feeding a creek in July. Provide question stems on cards for the sticky note activity, such as "Did ___ change over these years?" and "How would we measure ___?"

Extensions

Have students write a one-paragraph memo to the town of Wintershaw water board recommending one measurement the town should begin collecting now so that the next generation of planners has better evidence than this record provides. Ask them to state what the measurement is, how often it would be taken, and what question it would help answer.