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Lesson plan Grade 10 English Language Arts

The Redbud Plant's Jar-Test Procedure: A Technical Reading Lesson

A grade 10 lesson where students read a fictional treatment plant's jar-test standard operating procedure and write an explanatory summary for new hires.

Objectives

  1. Students will identify the sequential steps of a technical procedure and any stated exceptions.
  2. Students will convert a numbered technical procedure into a clearly organized explanatory paragraph.
  3. Students will use precise technical vocabulary correctly in their own writing.

Vocabulary

Turbidity
Turbidity is a measure of how cloudy or murky water looks because of tiny particles floating in it. Clear water has low turbidity, and muddy water has high turbidity.
Jar test
A jar test is a small-scale experiment operators run in the lab before treating a whole tank of water, testing different amounts of chemical in separate jars to see which dose clears the water best. It helps operators avoid wasting chemicals or under-treating the water.
Flocculation
Flocculation is the slow, gentle stirring step at a water plant that lets tiny sticky particles bump into each other and clump into bigger pieces called floc, heavy enough to settle out of the water.

Also: coagulant, standard operating procedure

Teacher overview

The fictional Redbud Water Treatment Plant runs a jar test twice a day to find the smallest dose of coagulant that will clear the raw water arriving at its intake, and its lab keeps a written standard operating procedure so that any technician on shift can run the test the same way. This lesson gives students that procedure as a genuine piece of workplace technical writing, a numbered sequence of steps with one stated exception, the kind of text a new employee has to read carefully and follow exactly. Students then convert what they read into a different genre, an explanatory paragraph a supervisor could hand to a first-week hire, which asks them to select and organize the procedure's ideas rather than copy its wording. The plant aims to bring its treated water below the federal government's turbidity benchmark of 0.3 NTU, the treatment-technique limit that conventional filtration plants must meet in nearly all monthly samples, so the jar test has real consequences for whether the plant's finished water will pass inspection.

Procedure

Hook (5 min): Ask students to recall a time they assembled something from a numbered instruction sheet and skipped a step by accident, and what happened as a result. Explain that today's text is a real category of workplace document called a standard operating procedure, or SOP, and that skipping a step or an exception in a water treatment SOP can mean a plant fails to meet its water quality standard.

Direct instruction (10 min): Distribute the fictional Redbud Plant's jar-test SOP (Student Handout). Read the first three steps aloud as a class, modeling how a careful reader tracks a numbered sequence: underline the action verb in each step, and circle any number that has to be measured exactly. Point out that step 7 contains an exception, a rule that applies only under a specific condition, and ask students to predict why a plant would write an exception into its own procedure.

Guided practice (15 min): In pairs, students read the remaining steps of the SOP and complete a two-column chart headed "What the technician does" and "What could go wrong if this step is skipped or done out of order." Circulate and check that pairs have correctly identified the exception in step 7 before moving to independent practice.

Independent practice (15 min): Each student drafts a single explanatory paragraph, written as if for a new hire's first day, that describes the jar-test procedure in their own words. The paragraph must state the purpose of the test, summarize the sequence of steps without copying the SOP's wording, and explain the step 7 exception in a sentence a new employee could actually follow.

Closure / exit ticket (5 min): Students answer three quick questions on an index card: (1) What is the purpose of the jar test? (2) Which step contains an exception, and what is it? (3) Why does a plant bother writing down a procedure instead of training technicians by word of mouth alone? Collect and scan for the exception (step 7) before dismissal.

The Redbud Plant's Jar-Test Procedure: A Technical Reading Lesson — Grade 10 English Language Arts
Name: ____________________________ Date: ______________

Student Handout

This is the fictional Redbud Water Treatment Plant's written procedure for its twice-daily jar test, used to find the coagulant dose that clears water most efficiently before it moves to sedimentation and filtration.

Redbud Water Treatment Plant -- Jar Test Procedure

  1. Collect a fresh raw-water sample from the plant intake and pour 200 mL into each of six test jars.
  2. Record the raw water's starting turbidity, in NTU, using the bench turbidimeter before adding any chemical.
  3. Add a different coagulant dose to each jar, in this order: 5, 10, 15, 20, 25, and 30 milligrams per liter, starting with the lowest dose in Jar 1.
  4. Stir all six jars rapidly for one minute so the coagulant mixes evenly, then slow the mixer to a gentle stir for ten minutes to let floc particles form and grow.
  5. Turn off the mixer and let the jars settle undisturbed for twenty minutes.
  6. Measure and record the settled turbidity in each jar.
  7. Identify the dose that produces the lowest settled turbidity at or below the plant's treatment target. Exception: if the next-lower dose also meets the target and reads within 0.1 NTU of that dose, choose the lower dose, since it costs the plant less in chemical without a meaningful difference in water clarity.

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: To find the lowest coagulant dose that clears the raw water before it moves on to filtration.
    The SOP's opening line and step 7 both establish that the test weighs water clarity against chemical cost, not simply any dose that works.
  2. Answer: Step 7. If the next-lower dose also meets the target and lands within 0.1 NTU of the best-performing dose, the technician chooses the lower dose.
    Step 7 is the procedure's only stated exception, and it exists to save chemical cost when two doses perform almost identically.
  3. Answer: A written procedure lets any technician on any shift run the test the same way, producing results that can be compared and trusted.
    Accept any answer that connects consistency, training new staff, or comparability of results across shifts to the reason a plant would formalize a spoken practice into a written SOP.

Differentiation

Support (below grade level)

Provide the two-column chart with the first row already filled in as a model ("Step 1: collects a fresh sample / Skipping this step means testing water that no longer represents what's arriving at the plant"), and let students complete their explanatory paragraph as a five-sentence frame with the first word of each sentence already supplied.

Extension (above grade level)

Ask students to redraw step 7 as a flowchart with a yes/no decision point, then explain in a short paragraph why a flowchart sometimes communicates an exception more clearly than a numbered list does.

ELL supports

Pre-teach "coagulant," "turbidity," "flocculation," and "standard operating procedure" with a labeled diagram of the jar test (cloudy water, six jars, settling, clearer water) before students read the SOP. Allow the two-column chart in guided practice to be completed with short phrases instead of full sentences.