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Classroom activity Grade 11 Art & Music

Tideport Beach Advisory Icons: A Blind Test Activity

Grade 11 students draw candidate advisory icons for a fictional coastal town, then run a randomized blind comprehension test on classmates and revise from the tallies.

Objectives

  1. Students will draw candidate icons that carry one message without words.
  2. Students will design and run a randomized comprehension test on their own icons.
  3. Students will revise an icon using evidence from the tallies rather than preference.

Vocabulary

Key words: comprehension test, randomize, sample survey, icon, revision

Teacher overview

Coastal towns post water contact advisories after heavy rain, when runoff carries bacteria into the surf, and the sign has to work for a visitor who is already halfway to the water. This activity puts groups of three through a classroom version of the comprehension testing that graphical symbols go through before they are adopted. Each group draws three candidate icons for the fictional town of Tideport, hides them, and then shows them one at a time in a randomized order to testers from another group, recording what each tester says the icon means. The blind format is what makes the evidence usable, because a group cannot argue for its favorite drawing once the tally sheet shows what testers actually read. Results depend entirely on the class that runs the test, so the key here accepts any answer that is consistent with a group's own recorded data.

Activity Directions

  1. Setup and briefing (7 min). Form groups of three and hand out index cards, markers, the handout, and one folder per group. State the single message every candidate icon has to carry: today the water at this beach is not safe for swimming. Tell groups that no words, letters, or numbers may appear on the icon itself, since the finished sign carries its text separately.
  2. Sketching round (15 min). Each group drafts at least six rough ideas on scrap, then commits its three strongest to index cards, one icon per card, drawn in black only. Groups place the three cards in the folder as soon as they are finished and complete handout items 1 through 3.
  3. Test design (5 min). Groups complete handout items 4 and 5, writing the exact question a tester will hear and deciding how they will shuffle the cards so the order changes for every tester. Check each group's question before testing begins, because a question that names the beach gives the answer away.
  4. Blind test rounds (15 min). Pair each group with another group, then rotate to a second partner group, so that each group presents its icons to two other groups. Testers view one card at a time, answer the question aloud within five seconds, and move on. The presenting group records every answer word for word on the tally sheet. Within each pairing, groups swap roles so that every group both tests and is tested. The round ends when each group has recorded at least six testers.
  5. Tally and revision (10 min). Groups complete handout items 6 through 9, then redraw their strongest icon once, changing only the single feature the tallies point to, and answer items 10 and 11.
  6. Debrief (8 min). Ask three questions and take answers from at least four groups. Which icon was read as intended most often, and what did it show? What was the most common wrong reading in the room? Would the result hold for visitors at a real beach, and what makes you say so?
Tideport Beach Advisory Icons: A Blind Test Activity — Grade 11 Art & Music
Name: ____________________________ Date: ______________

Student Handout

The fictional town of Tideport posts an advisory sign at its public beach when the water is not safe for swimming. Your group is designing the icon for that sign. Answer every item from your own group's work and your own recorded tallies.

  1. Describe each of your three icons in one sentence, and name the single message all three have to carry.
  2. Name the quantity your group will record for each tester: whether the reading was correct, how long the tester took to answer, or both. Explain the choice in one sentence.
  3. Name one thing you deliberately left out of your icons, and say why.
  4. Explain how you will shuffle the cards so each tester sees a different order, and say why the order matters.
  5. Write, word for word, the question every tester will hear.
  6. Record your tally: for each icon, how many testers read it as intended, out of how many testers.
  7. Which icon was read as intended most often? Give the tally that supports your answer.
  8. Is this test a sample survey, a controlled experiment, or an observational study? Justify your classification.
  9. Quote one wrong reading a tester gave, and name the part of the drawing that produced it.
  10. Name the one feature you changed in your revision, and predict how the tally would move if you tested again.
  11. Explain one reason your classmates may not represent the people who visit a beach.

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: Accept any three clear descriptions in which all three icons carry the same single message, that the water is unsafe for swimming today. Reject a set where one icon means a different thing, such as a general no-entry symbol or a pollution symbol with no reference to contact with the water.
  2. Answer: Accept either quantity, or both, with a reason that fits it. Correct readings suit a group asking whether the icon communicates at all. Response time suits a group asking how fast it reads at a distance. Reject an answer that names a quantity the group did not actually record.
  3. Answer: Accept any deliberate omission with a stated reason, such as leaving out a sun, a lifeguard, or a bacterial shape because it added detail without carrying the message.
  4. Answer: Accept any method that changes the order for each tester, such as shuffling face down or drawing cards blind from an envelope. The reason should note that a fixed order lets a later card benefit from what the tester already worked out.
  5. Answer: Accept any neutral wording, such as "What does this picture tell you to do?" Reject a question that names the beach, the water, or safety, since it supplies the answer.
  6. Answer: Accept the group's recorded tallies, provided each icon has a count of intended readings and a count of testers, and provided the two counts are consistent across all three icons.
  7. Answer: Accept whichever icon the group's own tally supports, with the numbers quoted. Reject an answer that names a favorite icon the tally does not support.
  8. Answer: Accept a sample survey or an experiment if justified. A survey answer argues that testers are simply asked what each icon means. An experiment answer argues that the group imposes the icon conditions on each tester and randomizes their order to compare the icons. Reject an observational study, since the group controls what testers see.
  9. Answer: Accept any quoted wrong reading paired with a specific feature of the drawing, such as a wave shape read as wind or a crossed circle read as a closed beach rather than unsafe water.
  10. Answer: Accept any single named change with a prediction, such as thickening the figure so it reads at a distance, and a stated expectation about the count of intended readings.
  11. Answer: Accept any reason grounded in who was tested, such as classmates having already discussed the topic, sharing an age range, or seeing the icon on a card at arm's length rather than on a post at the shoreline.

Differentiation

Support

Give the group a starter sheet with three unfinished icon fields already ruled and a printed tally grid with the rows and columns labeled, so recording is not a second task during the test. Provide a model question for item 5 and one worked classification for item 8 using a different example, then ask the group to write its own.

Extension

Ask a group to add a second test in which each icon is shown for one second only, then to compare the two sets of tallies and state what the shorter exposure revealed. They should also write a short recommendation to the town, naming the icon they would adopt, the evidence behind it, and the one condition under which they would want a larger test before deciding.

ELL supports

Pre-teach icon, tally, randomize, and survey with a labeled example and keep it posted. Allow testers to answer in their strongest language, with a group member recording the response and a short English gloss beside it. Provide the frame "Testers thought this icon meant ___ because the drawing showed ___," and allow items 9 through 11 to be answered with an annotated sketch and a short phrase.

Extensions

Have groups design the full sign around the winning icon, adding the text block, the town identifier, and the date line, and stating the type sizes. Ask them to keep the icon dominant and to explain in one sentence how the layout preserves that dominance. Groups can then compare their sign against the advisory signage their own state or county actually posts, and note one difference worth asking a public health office about.