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Worksheet Grade 9 English Language Arts

Editing a Water Quality Lab Report for Precision: Grade 9 Worksheet

A grade 9 technical writing worksheet where students revise a fictional lab technician's vague drafts into precise, regulation-accurate water quality sentences.

Objectives

  1. Students will revise vague or imprecise sentences in a lab report into precise technical statements supported by exact figures.
  2. Students will identify and correct unnecessary passive voice in technical writing.
  3. Students will combine choppy sentences into clear, well-connected technical prose.

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.
Dissolved oxygen
Dissolved oxygen is the oxygen gas mixed into water that fish and other underwater animals breathe. Cold, moving water holds more oxygen than warm, still water.

Also: maximum residual disinfectant level, precision

Teacher overview

Water testing laboratories send monthly reports to state regulators, and those reports are only useful when they state exact figures rather than casual descriptions. This worksheet asks students to revise a lab technician's rough draft notes into the precise technical language a real report requires, practicing sentence-level revision alongside vocabulary drawn from water testing and water chemistry. A common habit this worksheet corrects is the default use of hedging phrases such as "pretty good" or "kind of high" when a writer has not yet turned data into a sentence; students learn to replace that habit with wording anchored in the report's actual measured values.

Editing a Water Quality Lab Report for Precision: Grade 9 Worksheet — Grade 9 English Language Arts
Name: ____________________________ Date: ______________

Student Worksheet

Imagine a lab technician named Jordan Ruiz drafted the following notes for a fictional laboratory called Clearwater Testing Lab, before sending the report on to a state regulator. Your job is to revise Jordan's vague draft sentences into precise, accurate ones.

  1. The draft report says: "The turbidity was fine." The regulation requires finished water to stay at or below 0.3 NTU in 95 percent of monthly samples. Jordan's lab measured 0.2 NTU that day. Revise the sentence into one precise sentence that states the measured value and compares it to the standard.

  2. The draft report says: "The pH seemed okay." The secondary standard for drinking water pH is 6.5 to 8.5. Jordan's lab measured a pH of 7.2. Revise the sentence into one precise sentence.

  3. The draft report says: "Chlorine levels were kind of high this week." The maximum residual disinfectant level for chlorine is 4.0 mg/L. Jordan's lab measured 3.8 mg/L. Revise the sentence into one precise sentence that makes clear the reading stayed under the limit.

  4. The draft report says: "Dissolved oxygen was low for the fish." Most fish need dissolved oxygen above 5 mg/L. Jordan's lab measured 3.5 mg/L. Revise the sentence into one precise sentence explaining what that reading means for fish in the receiving stream.

  5. Of the four vague sentences above (turbidity, pH, chlorine, dissolved oxygen), which one uses the least precise language, and why?

  6. In one sentence each, explain the difference between a "regulatory standard" and a "measured value," using two numbers from the report as your example.

  7. The draft report ends with: "Overall things looked pretty good this month." Rewrite this sentence into one precise summary sentence that cites at least two of the four measurements above.

  8. The draft report includes this sentence: "It was noted that the turbidity reading was taken at 9 a.m." Identify the passive-voice construction and rewrite the sentence in active voice, naming Jordan Ruiz as the technician who took the reading.

  9. The draft report includes these two short sentences back to back: "The pH reading was normal. The chlorine reading was also normal." Combine them into one clear sentence using a connecting word such as "and" or "while," rather than leaving them as two short, choppy sentences.

  10. Explain in two or three sentences why a state regulator reading this report would need precise numbers rather than words like "fine," "okay," or "pretty good."

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: The measured turbidity was 0.2 NTU, below the 0.3 NTU limit for finished water. A correct revision states both the measured value and the standard it is compared against, in one clear sentence.
  2. Answer: The measured pH was 7.2, within the 6.5 to 8.5 secondary standard for drinking water. A correct revision states both numbers rather than the word "okay."
  3. Answer: The measured chlorine level was 3.8 mg/L, below the 4.0 mg/L maximum residual disinfectant level. A correct revision makes clear the reading did not exceed the limit, since "kind of high" could mislead a reader into thinking it did.
  4. Answer: The measured dissolved oxygen was 3.5 mg/L, below the 5 mg/L level most fish need, meaning fish in the receiving stream could be under stress. A correct revision states the measured value, the benchmark, and what the gap means.
  5. Answer: Accept reasoned answers. A strong response picks one of the four sentences and explains the choice. For example, "The turbidity was fine" and "The pH seemed okay" give no direction or number at all, while "kind of high" and "low for the fish" at least signal a direction.
  6. Answer: A regulatory standard is the fixed number a report is checked against, such as the 0.3 NTU turbidity limit; a measured value is the actual number recorded that day, such as the lab's 0.2 NTU reading.
  7. Answer: Accept any precise sentence citing at least two of the four measurements, for example: "Turbidity measured 0.2 NTU and dissolved oxygen measured 3.5 mg/L this month, with turbidity staying well under its limit while dissolved oxygen fell below the level fish need."
  8. Answer: The sentence has two passive constructions, "It was noted that..." and "was taken." Accept either, and give full credit for naming both. A correct active revision is: "Jordan Ruiz took the turbidity reading at 9 a.m."
  9. Answer: Accept any combined sentence that uses a connecting word, for example: "The pH reading was normal, and the chlorine reading was also normal," or "Both the pH and chlorine readings came back normal."
  10. Answer: Accept reasoned answers. A strong response explains that words like "fine" or "pretty good" cannot be checked against a legal standard, while a specific number lets a regulator confirm compliance directly and hold the utility accountable if a reading is ever out of range.

Differentiation

Support (below grade level)

Provide item 1 fully revised as a model ("The measured turbidity was 0.2 NTU, well below the 0.3 NTU limit for finished water.") before students attempt items 2 through 4 on their own, and allow items 5, 6, and 10 to be answered orally instead of in writing.

Extension (above grade level)

Ask students to draft one additional vague sentence of their own, in the style of Jordan's original notes, using one of the four measurements, then trade with a partner and revise each other's sentence for precision.

ELL supports

Pre-teach "turbidity," "residual," "precise," and "vague" with simple definitions and one example sentence each before students begin. Allow items 1 through 4 to be answered using a sentence frame: "The measured [term] was ___, which is [above/below/within] the standard of ___."