Grades 6–8 · Seasons & change
Seasons of the Water: watching a pond change with the class
One vial, one waterway, tracked across the school year to see who comes and goes.
Students predict how seasonal change will shift which species use a local pond or stream, run a whole-class composite sampling protocol on one vial, and compare the class Field Journal results to their seasonal predictions.
Grade band
Grades 6–8
Time required
4 class periods (spread across a season)
Class size
20–32 students, one kit
Sample type
Water, one vial
Standards and outcomes
- MS-LS2-1 — Analyze and interpret data to provide evidence for the effects of resource availability on organisms and populations
- MS-LS2-4 — Construct an argument supported by evidence for how changes to physical or biological components of an ecosystem affect populations
- MS-ESS2-6 — Develop and use a model to describe how unequal heating and rotation of the Earth cause patterns of atmospheric and oceanic circulation that determine regional climates and seasons
- Science & Engineering Practices — planning investigations, analyzing data, developing models, constructing explanations, engaging in argument from evidence
How one kit serves a whole class
The $200 Classroom Starter Kit holds one collection vial, targets up to five species, and returns results in 7–10 days into the class Field Journal. The whole class shares the single sample by using a composite batching protocol: several crews each pull a sub-sample from a different spot at the water's edge, and all sub-samples are pooled into the one vial, so every student contributes to the sample that represents the site during this season.
Choose one
Research tracks
Track A — Who Shows Up in Spring
Seasonal arrival and breeding cycles
Driving question. Which species become active or return to our pond as the water warms?
Species to pick. Up to five species tied to seasonal water activity: a pond-breeding amphibian (frog or salamander), a migratory or seasonally active waterbird, a native fish, a turtle that becomes active as temperatures rise, and an aquatic insect linked to spring hatch cycles.
What students take away. Students connect detection or non-detection to temperature-driven life cycles like breeding, migration, and emergence.
Track B — Who Disappears in Fall
Seasonal decline and dormancy
Driving question. Which species become harder to detect as the water cools?
Species to pick. Species expected to become dormant, migrate away, or reduce activity in cooler water: a cold-sensitive fish, an amphibian that burrows for winter, a bird that migrates south, and a warm-season aquatic insect.
What students take away. Students use a drop in relative signal as evidence of dormancy or migration rather than local extinction.
Track C — Same Site, Two Seasons
Comparing repeated composite samples over time
Driving question. How much does our site's detectable community actually change between two seasons?
Species to pick. A mixed list of five species chosen to include some expected to persist year-round and some expected to shift seasonally, so the class has both a stable baseline and a changing signal to compare.
What students take away. Students build a before/after comparison chart and argue which changes are seasonal versus which might be noise.
The lesson sequence
Step by step, with teacher notes
- 01
Predicting the season's community
45 minutesStudents research the site and the time of year, then propose and vote on five target species tied to seasonal patterns. Each student records a dated prediction before any sample is collected.
Teacher notes
- Open with: "We only get five slots on this kit — argue for the species that will actually tell us something about the season."
- Bring a simple seasonal calendar for the region (breeding months, migration windows, dormancy periods) so predictions are grounded, not guesses.
- Require each proposal to include a reason tied to temperature, daylight, or breeding cycle, not just 'I think it lives here.'
- Run the vote and record the final five species and the date, since this list will be revisited later in the year.
Materials
- Regional seasonal activity calendar
- Whiteboard or shared doc for the vote
- Dated prediction log sheet
Student prompts
- What is happening to the water temperature and daylight right now, and how might that affect this species?
- Would you expect this species to be more or less detectable at this time of year? Why?
- What would surprise you if it showed up or didn't show up in the results?
- 02
Composite sampling at the water's edge
50–60 minutesThe whole class contributes to one vial. Crews pull sub-samples from several spots along the shoreline and pool them into a single composite sample that represents the site at this moment in the season.
Teacher notes
- Say before anyone touches gear: "Gloves on first — if a glove touches the ground, the vial's inside, or your face, swap it out."
- Walk the site ahead of time and mark three or four collection spots that differ in sun exposure, depth, or vegetation.
- Rotate every student through at least one role (sampling, recording, temperature check, sealing) so the class understands the composite sample was a group effort.
- Record the exact date and weather conditions carefully — this data point is what makes the seasonal comparison possible later.
- Have a rain-date plan ready; a storm the week of collection can change what's detectable.
Materials
- 1 classroom eDNA collection vial and prepaid mailer
- Nitrile gloves (one pair per student minimum)
- 3–4 sterile sub-sample cups
- Thermometer
- Field data sheet on clipboard
Student prompts
- Sampling crew — collects sub-samples from three or four distinct shoreline spots.
- Recording crew — logs date, time, air and water temperature, and weather.
- Sealing crew — pools the sub-samples, seals the vial, and preps the return mailer.
- 03
What the lab does while we wait
40 minutes, during the 7–10 day turnaroundWhile the sample travels to the lab, students learn how a genetic detection actually works and why timing and temperature matter so much to what gets detected.
Teacher notes
- Say: "This waiting period is part of the science — the lab is running the sample through several careful steps right now."
- Sketch the pipeline simply: collect → extract DNA → copy target sections → match against a reference list → report results.
- Explain that DNA in water breaks down within a few days, so a detection means the species was there very recently.
- Ask students to revisit their Phase 1 predictions and note if anything they've learned this week changes their thinking.
Materials
- Simple diagram of the lab process
- Vocabulary handout (DNA, detection, degradation, reference match)
Student prompts
- Why does a genetic detection tell us a species was recently present, not present right now?
- How might warmer water speed up or slow down DNA breakdown?
- Has anything changed about your prediction since Phase 1? Why or why not?
- 04
Reading the Field Journal and comparing to predictions
45 minutesThe class opens the Field Journal together, compares actual detections and relative signal strength to their seasonal predictions, and builds a simple claim about how the season shaped the results.
Teacher notes
- Reveal the results as a class event — project the Field Journal and read it out loud together.
- Have students mark their predictions as matched or not matched before discussing why.
- Ask: "Which result best supports the idea that season changes what we can detect?"
- Push students to use the word 'relative signal' correctly, not just 'amount' — it's about the strength of the genetic detection, not a body count.
- If your class plans a second sampling later in the year, save this Field Journal for direct comparison.
Materials
- Class Field Journal report (projected)
- Prediction log sheets from Phase 1
- Simple claim-writing frame
Student prompts
- Which of your predictions were supported by the Field Journal results?
- Which detection surprised you most, and what season-related reason could explain it?
- Write one sentence claiming how season affected what we detected, and one piece of evidence to back it up.
Student handout
For every student
Thinking prompts
- Write your prediction for each of the five target species before the sample is collected.
- Explain the seasonal reasoning (temperature, daylight, breeding, migration) behind each prediction.
- Describe, in order, how your crew contributed to the composite sample.
- Explain why a detection means a species was recently present rather than present right now.
- Predict one species you expect will NOT be detected this season and explain why.
- After the reveal, mark which predictions were supported and which were not.
- Name one thing you would sample differently next season.
Data sheet
- Date and time of collection:
- Site name or description:
- Air and water temperature:
- Weather conditions on collection day:
- Number and location of shoreline sub-samples:
- Any wildlife directly observed on site:
- Target species list with pre-reveal predictions:
Discussion questions
- Why might a species be detectable in one season but not another?
- What does 'relative signal' mean, and why isn't it the same as counting individual animals?
- How could weather in the days before sampling affect what we detect?
- If we repeat this sample next season, what result would most surprise you?
Field checklist
- Nitrile gloves worn before touching any sampling equipment.
- Sub-samples collected from at least three distinct shoreline spots.
- Date, time, air and water temperature recorded.
- Weather conditions logged on the data sheet.
- Sample pooled, sealed, and labeled without touching the inside of the vial.
- Predictions recorded in writing before results were revealed.
Analysis
CER: Did the season change what we detected?
- 1.Claim — write one sentence stating whether season affected the site's detectable species.
- 2.Evidence — list specific relative signal values and the temperature/weather conditions recorded at collection.
- 3.Reasoning — explain how each species' life cycle (breeding, migration, dormancy) connects to the evidence.
- 4.Counter-evidence — identify one result that doesn't fit your claim and explain a possible reason.
Assessment
20-point rubric
Seasonal prediction and reasoning
6 ptsEach of the five species predictions is grounded in a clear seasonal or temperature-based reason.
Field procedure and data logging
5 ptsComposite sampling steps were followed correctly and site conditions were fully recorded.
Reading the Field Journal
4 ptsDetections and relative signal values are interpreted accurately and matched against predictions.
CER conclusion
5 ptsThe written claim is clearly supported by specific evidence and sound seasonal reasoning.
Go further
Extensions
- Order a second kit next season and build a direct before/after comparison chart of the same five species.
- Graph the class's water temperature readings against detection results across multiple sampling rounds.
- Invite students to research one detected species' full seasonal life cycle and present it to the class.
- Compare seasonal results with a partner class at a different site to see whether the same seasonal pattern holds elsewhere.
For the teacher
Answer key and misconceptions
- Expected: species tied to breeding or migration will show stronger or weaker signal that lines up with the season sampled; discuss any mismatch as a discussion point rather than an error.
- Common misconception: 'no detection means the species is gone.' Correct framing: it may simply be dormant, migrated, or below the detection threshold at this time of year.
- Common misconception: 'strong signal now means the population grew.' Correct framing: relative signal reflects how much DNA was shed recently, which can shift with activity level, not just population size.
- Expected: students should be able to explain that DNA degrades within days, so results describe recent presence tied closely to the sampling date, which is exactly why season matters.