Students will learn to use the basics of several scientific sampling techniques to make generalizations about their vital signs study area. Students will learn about the importance of sample size as they compare plots within and across Vital Signs study areas.

• 3-4:
  • 1. Make accurate observations using appropriate tools and units of measure.
  • 5. Explain how differences in time, place, or experimenter can lead to different data.
  • 6. Explain how different conclusions can be derived from the same data.
• 5-8:
  • 1. Make accurate observations using appropriate tools and units of measure.
  • 5. Explain how personal bias can affect observations.
• 9-12:
  • 1. Make accurate observations using appropriate tools and units of measure.

• Comparing
• Describing
• Contrasting
• Differentiating
• Examining

The class must be able to use the Vital Signs equipment including protocols for data collection.

• Linguistic/verbal
• Naturalistic
• Visual/spatial

• Vital Signs tools (Palm with VS software, calibrated temperature probe, camera, GPS)
• surveyor's tape
• 1m² frames (e.g. 4-1m lengths of PVC piping, a 4 m string with knots at each meter mark) -or- meter sticks and masking tape
• 5m rope or 20m rope with 5m markings
• 1000-2000ml water
• 5 7cm soup cans without tops or bottoms
• maps of local Vital Signs study area(s) - road, topographic, geological (Maine Geological Survey)
• Optional:
  identification guides to planets, tress, etc
  identification guide to soil

The disciplines of math and science provide wonderful tools to help us understand our world. While some of these tools are physical, others are conceptual. Statistics, including sampling along "transects" and use of "quadrats," are some of these tools.

For reference a "transect" is a sampling area usually defined as a straight line. Transects can be taken in random directions or chosen specifically, as here, to show difference from one area to another (lowland to upland). Samples can be taken along the entire length or at discrete points, such as with the use of "quadrats" - smaller, .25m² to 1m² sampling areas used for ecological or population studies.

While proper use of these and similar sampling methods can be quite complex and require a fair amount of background work to fully understand, students will benefit from exposure to both the techniques and science observation's fundamental tenet - that whatever method of observation is used, it is crucial that the student/scientist clearly explain how observations were made.

PART I - Virtual Data Gathering (Indoors, 90 minutes)

NOTE: The first part of this activity is best performed before visiting the Vital Signs study site(s).

1. Using maps (political, topographical, geological) of your class' Vital Signs study site(s), ask each of five student groups to locate and estimate latitude, longitude, and elevation above sea level and mark these on their site data sheet under "prediction".
2. In addition to these site locators, ask students to thoughtfully predict the following to the best of their ability:
   • Average Ground Slope (flat, moderate, steep)
   • Forest Canopy Cover (% shade - 0, 25, 50, 75, 100%)
   • Ground Coverage (woody, herbaceous, grass, forest litter/decaying plants, other) within 20 meters of water
   • Soil Type/Texture (rock, sand, silt/clay, organic)
   • Soil Moisture content (dry, moist, wet)
   • Soil Percolation/Drainage (low, medium, high)
   • Estimated soil temperature at the surface and at 10cm depth given air temperature at the school.
3. Timed Writing/Drawing - Ask students to each describe, with words and/or drawing, the site as they expect it might actually appear. Set an appropriate maximum of time to complete the activity (5-10 minutes). When finished, have students read and/or show their descriptions to each other and choose one to present.
4. Using the above predictions, ask students to present their descriptions of the site(s) including an explanation of how they made their predictions.

PART II - Field Observations (Vital Signs Study Site(s), 90 minutes)

1. At the Vital Signs Study Site(s), give each student team a Vital Signs hardware set, and a way to mark a 1 m² area (the PVC pipes, 4 m long measured string, or meter stick and masking tape).
2. Define approximately 20m of "transect" perpendicular to and away from your water source. Consider marking the beginning and end of the transect with surveyors tape.
3. Ask the first group to randomly drop their quadrat along this line within a meter of the water's edge. If the square leans against a tree, bushes, etc., tell students that they must leave the quadrat where it is. If you only have meter sticks, ask students to drop the meter stick and define the remaining two corners of their quadrat using a predetermined method. While masking tape may be useful to mark the corners, natural objects may work just as well for now.
4. Measure out 5m beyond the first group and have the second group drop their quadrat along the transect. Continue dropping quadrats at 5m intervals for the remaining three groups.
5. 5. Ask students to take measurements and make observations on data sheets, ONLY within their 1m2 quadrat. Ask them to include:
   • Latitude, Longitude
   • Average Ground Slope (flat, moderate, steep)
   • Forest Canopy Cover (% shade - 0, 25, 50, 75, 100%)
   • Ground Coverage by Percentage of Woody Plant, Herbacious Plants, Grass, Moss/Lichen/Fungi, Decaying Plants/Forest Litter, Open Area. NOTE: Older students may be able to sub-categorize plants to family or even genus/specis. However, for cross-site comparison, make sure to also assign percentages to the categories above.

   To simplify the process students may have to give no/yes or 0/1 results instead of percentages. "Presence/Absence" is a valid means of data collection under certain conditions. If 0/1's are used, the numbers can also be averaged and turned into a percent. Also, the 1m2 grid can be divided into 2x2 or 10x10 squares using string and/or painting the quadrats at appropriate distances.

   • Soil Type/Texture (rock, sand, silt/clay, organic)
   • Soil Moisture content (dry, moist, wet)
   • Soil Percolation/Drainage (low, medium, high). To measure this, place the open-ended can in the center of the quadrat. While pressing firmly against the surface, add 200ml water and time how long it takes for all water to completely absorb into the ground.
   • Temperature 1m above the ground, at the surface, and at 10cm depth.
   • Images of the quadrat ground area, sky directly above, and four directions parallel to the ground and inline with the transect.
   • Any special notes or observations about their quadrat not mentioned above such as special plants, evidence of animals, recent weather or other activity that might affect observations, etc.

PART III - Characterizing and Comparing Vital Signs Study Site(s) (Indoors, 90 minutes)

After making copies of student data sheets and passing out to all groups, ask each student in each of the five groups to:

1. Copy all data onto one sheet.
2. Characterize their Vital Signs Study Site(s) by averaging and/or determining a range for each character.

   NOTE: Depending on grade level, you may want to run through each character with the class or give examples and compare student results as a means of talking about "averaging."

   Returning to groupsŠ

4. 3. Have each student group summarize their "averages" and choose a "representative image" of the site.
5. 4. Ask student groups to present their site summary to the class including an explanation of how they determined their results and why they chose the image they did.
6. 5. Discuss site summary differences between groups including method of averaging, error, perspective, and topography.
7. 6. As a class create a common site characterization which takes into account differences mentioned and discussed during presentations.
8. 7. Add the site characterization information, along with number of quadrats taken, to the Vital Signs web site.
9. 8. Points of discussion:-How would adding more transects and quadrats change characterization of the site?-How did your predictions compare to taking "real data?"-How many data points do you need to be "accurate."-Can you take too much data? Why not just count everything?

• Use the Vital Signs website to compare the class study site to other sites.
• Consider setting up a messaging system with another Vital Signs school/site using email, IM, etc. to facilitate this comparison.
• Perform additional perpendicular transects at 20m intervals along the water's edge to refine the study site's description. Discuss how adding additional data refines the site characterization. At what point is the site described "well enough?"
• Create a panoramic image of the the Vital Signs study site(s) at water's edge and 20m perpendicular to and away from the water edge. Post this to the Vital Signs website.
• Consider using the canopy and/or ground images to analyze the actual area of canopy and/or ground cover. Free programs for this kind of analysis can be found at .
• Read place-based nature writing to discuss the power of observation. Examples include:
  • Waldon Pond
  • The Pilgrim at Tinker Creek, and
  • Neighborhood Puddles

NOTE: We may need to take excerpts from one or more of these works to simplify this extension for interested teachers.