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Lesson plan Grade 11 Art & Music

Stonecross Rainfall Bands: A Woven Data Lesson

Grade 11 students encode a year of fictional rainfall as stripe widths on a woven band, choosing a scale that fits a fixed warp length.

Objectives

  1. Students will convert a year of monthly rainfall totals into stripe lengths at a stated scale.
  2. Students will select a scale that fits the encoded band inside a fixed warp length.
  3. Students will explain why every stripe on the band must share one scale.

Vocabulary

Key words: warp, weft, encode, scale, band

Teacher overview

Weaving encodes information the way a bar chart does, because a stripe's length along the warp is a measured quantity rather than a decorative choice. In this lesson students weave a narrow band whose stripes record a year of monthly rainfall at the fictional Stonecross gauge, so the finished textile can be read as data. The design problem is a real one: the loom's usable warp is shorter than the most obvious scale requires, so students have to choose a smaller scale rather than trimming a month. The misconception to address directly is that a stripe can be shortened for craft reasons without changing what the band reports, since one altered stripe changes what the whole band says about the year. The monthly totals stand in for the record a hydrologic technician maintains at a gauge station, where a reported number is not adjusted to suit the format it appears in.

Procedure

Session 1, hook (8 min): Pass around two woven or paper-woven sample bands, one with stripes of equal width and one with stripes of varying width. Ask students what, if anything, the second band could be recording, and list their guesses without confirming any of them.

Session 1, direct instruction (12 min): Introduce warp and weft, and show that the length of a stripe along the warp is the only dimension free to vary once the loom is set up. Model one scale conversion on the board using numbers that are not on the handout, for example 5.0 inches of rain at 3 cm per inch giving a 15 cm stripe.

Session 1, guided practice (10 min): Students complete handout items 1 through 4 in pairs, testing the 2 cm per inch scale against the 60 cm warp and finding the total length at 1.5 cm per inch. Confirm answers as a class before anyone warps a loom.

Session 1, independent work (15 min): Students finish handout items 5 through 12 and draw a full-size stripe plan on a paper strip, marking every month boundary in pencil and labeling each stripe with its month and its length.

Session 2, studio work (35 min): Students warp their looms, then weave the band, checking each stripe against the paper plan before moving to the next month. Require the plan to stay taped beside the loom so the measurement is visible while weaving.

Session 2, closure and check (10 min): Each student lays the finished or partial band beside a neighbor's and answers one question in writing: "Name the month your neighbor's band shows as the wettest, and say how you can tell without asking." Collect the responses and confirm that at least three quarters of the class identified June, which is the true answer for this data set.

Stonecross Rainfall Bands: A Woven Data Lesson — Grade 11 Art & Music
Name: ____________________________ Date: ______________

Student Handout

The fictional Stonecross rain gauge recorded these monthly totals, in inches: January 2.1, February 1.8, March 2.6, April 3.4, May 3.9, June 4.2, July 3.1, August 2.8, September 2.5, October 2.2, November 2.4, December 2.0. Your loom's usable warp length is 60 cm. Use these numbers for every item.

  1. Add the twelve monthly totals. What is the year's rainfall total, in inches?
  2. You first plan a scale of 2 cm of woven band for every inch of rain. How long would the whole band be?
  3. Does the band from item 2 fit inside the 60 cm usable warp? Answer yes or no, and give the difference.
  4. You change the scale to 1.5 cm per inch. How long is the whole band now?
  5. At 1.5 cm per inch, how long is the June stripe?
  6. At 1.5 cm per inch, how long is the February stripe?
  7. How much longer is the June stripe than the February stripe at that scale?
  8. What is the largest scale, stated in whole tenths of a centimeter per inch, that still fits the band inside 60 cm?
  9. At the scale you found in item 8, how long is the whole band?
  10. Explain what goes wrong if you weave eleven months at 1.5 cm per inch and the twelfth at 2 cm per inch.
  11. Your band uses one color for cool months and another for warm months, and stripe length carries the rainfall. Explain what a reader loses if you also make wetter months darker.
  12. The gauge's mean monthly rainfall is 2.75 inches. Give one reason a designer might encode each month's departure from that mean instead of its total, and one reason to keep the totals.

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: 33.0 inches. Adding the twelve values in order gives 3.9, 6.5, 9.9, 13.8, 18.0, 21.1, 23.9, 26.4, 28.6, 31.0, and 33.0 inches.
  2. Answer: 66 cm. Multiplying the 33.0 inch total by 2 cm per inch gives 66 cm of band.
  3. Answer: No. The 66 cm band is 6 cm longer than the 60 cm usable warp, so the scale has to come down.
  4. Answer: 49.5 cm. Multiplying 33.0 inches by 1.5 cm per inch gives 49.5 cm, which fits with room left over.
  5. Answer: 6.3 cm. June's 4.2 inches multiplied by 1.5 cm per inch is 6.3 cm.
  6. Answer: 2.7 cm. February's 1.8 inches multiplied by 1.5 cm per inch is 2.7 cm.
  7. Answer: 3.6 cm. Subtracting the 2.7 cm February stripe from the 6.3 cm June stripe leaves 3.6 cm.
  8. Answer: 1.8 cm per inch. Dividing 60 cm by 33.0 inches gives about 1.818 cm per inch, so 1.8 is the largest whole tenth that fits, while 1.9 would need 62.7 cm.
  9. Answer: 59.4 cm. Multiplying 33.0 inches by 1.8 cm per inch gives 59.4 cm, which is 0.6 cm under the warp limit.
  10. Answer: The twelfth month would read as wetter than it was. A reader measures every stripe with the same key, so a stripe woven at a different scale reports a rainfall the gauge never recorded.
  11. Answer: The reader loses a clean second channel. Color already separates cool months from warm ones, so making wetter months darker doubles up on rainfall and leaves the reader unsure whether a dark stripe means warm, wet, or both.
  12. Answer: Departures show which months ran above or below normal, which suits a band about drought or surplus. Totals suit a band about how much water actually fell, and they keep the stripe lengths tied to a quantity the gauge measured directly.

Differentiation

Support

Provide the running totals for item 1 already computed in a column so students verify rather than accumulate, and pre-mark a paper strip at 1.5 cm intervals so stripe boundaries can be counted rather than measured. Pair each student with a partner who checks two stripe lengths against the plan before weaving begins.

Extension

Ask students to weave a second, narrower band for the same year at a scale of their own choosing and to write a short comparison of what changes and what stays true when the same data is encoded at two scales. Require them to state the scale in a woven or stitched label on each band, the way a chart states its axis.

ELL supports

Pre-teach warp, weft, stripe, and scale with the loom itself as the visual anchor, pointing to each part as the word is introduced. Provide a bilingual measurement card with centimeters and inches side by side, and allow items 10 through 12 to be answered in short phrases or with a labeled sketch of two bands.