Lesson Plan Template: General Lesson Plan
Learning Objectives: What should students know and be able to do as a result of this lesson?
- Explain how parasites can affect damselfish behavior.
- Explain the relationship between damselfish, reef cleaner species, and the gnathiids.
- Explain how scientific work is accomplished through field work, lab work, collaboration, and communication.
- Cite specific and relevant text evidence to support analysis of the text.
- Use vocabulary strategies to define academic and domain-specific words in the text.
- Determine a central idea of the text.
- Construct a written response that clearly establishes the main point(s), contains relevant textual evidence to support the main point, utilizes transitions to maintain flow, effectively uses domain-specific vocabulary, and provides an appropriate conclusion.
Prior Knowledge: What prior knowledge should students have for this lesson?
With regard to science content knowledge:
- To help students more fully understand the text used in this lesson, students should be familiar with components of a coral reef ecosystem including information about parasites, the role of cleaning stations on reefs, information about cleaner fish (gobies), and cleaner shrimp.
- Students should have prior knowledge of basic damselfish behavior, including aggressive defense of a territory where they defend their algae that is "farmed" as a food resource.
- Knowledge of fish broadcast spawning is also useful.
- Knowledge of symbiotic relationships including mutualism and parasitism is important for this article.
With regard to literacy skills:
- Students should have prior experience utilizing various vocabulary strategies to determine the meaning of unknown words in a text. For this lesson, prior experience in using context clues to determine the meaning of words in a text would be beneficial. In addition, students should have some dictionary skills that will enable them to look up words with multiple meanings and determine the most appropriate meaning based on how a word is used in a text.
- Students should understand the term "central idea" and be able to distinguish central ideas from key details.
- "Central idea" means the same thing as "main idea." The central idea is the author's main point about the topic or topics in a text. The central ideas are the dominant, most important, or chief ideas that emerge from all the ideas presented in a text. Students should be aware that the author can have several main points he or she wants to make about the topic or topics in a piece of writing, and as a result, there can be multiple central ideas in a text, especially in longer more complex pieces.
- Key, or in other words, important, details in a text help an author support and develop his or her central ideas.
- Students should be aware of text features that can help them locate and learn information when reading a text. The text features in the NSF article used in this lesson include: title, subtitle, headings, a photograph and caption.
- Based on the rubric provided with this lesson, students should be able to respond to a writing prompt in a clear, organized manner that includes use of an introduction to establish the main point(s), a body paragraph(s) that support the main point(s) and includes relevant and specific textual evidence, and a conclusion that supports the main point(s).
- Students should have some awareness that use of transition words or phrases can help a piece of writing flow smoothly from one point or idea to the next. Teachers might wish to provide students with a sheet of transitions to help them. This site provides transitions teachers might provide.
Guiding Questions: What are the guiding questions for this lesson?
1. What were the initial observations that led to the conclusion that parasites influence damselfish behavior?
If a female damselfish leaves her territory, there is a risk of losing it to other fish, as well as the possibility of having her food stolen. As a result, it is risky behavior when the female leaves her territory for an extended time. It was observed the damselfish would leave their territory to go to cleaning stations every morning and would even interrupt their spawning activity to visit a cleaning station near the spawning area. The author of the article realized there must be something worth the risk to the female that would cause her to do this. Eventually it was discovered that they had parasites removed at the cleaning station.
2. How were the gnathiid parasites identified?
The author observed what type of organism was being removed at the cleaning stations. He brought the specimens to parasitologists George Benz, Alexandra Grutter, Isabelle Côté and Nico Smit. They identified the organism as larval gnathiid isopods that act as a parasite on fish.
3. What is the lifestyle of a parasite and how successful is this lifestyle on a coral reef?
Parasites live on or in a host without intending to kill it. They depend on their host for their food source. The author claims that parasites are the most abundant of the inhabitants on the coral reef. (This statement is not specific and needs qualifiers. There are more symbiotic algae, zooxanthellae that live in the hard corals, and there are more bacteria than any other organism on the reef). *Here are some links to research being done on numbers of parasites on reef fish. The studies would provide general information on this topic because they are not specific to damselfish or Barbados.
4. Explain the characteristics of this parasite: the gnathiid isopod.
The gnathiid is interesting because it is the larval form that acts as a parasite and feeds on the blood. They actually do not feed as adults. They are also the primary food source for the cleaner fish in this reef system. They will usually attach themselves to fish during the night (as inferred by the fact that the heaviest infestation (load) occurs in the morning.
5. Once the question of what was influencing the behavior of damselfish was answered, what other questions arose?
The author was curious to discover if the gnathiid, like the mosquito and tick, can transmit blood borne parasites to other organisms. If this was the case, what organisms could be affected by the transmission of the disease?
6. How was the question of "Do gnathiids transmit disease?" answered?
Damselfish (and other fish species) were captured, anesthetized, blood samples were taken, and blood samples were prepared on slides to be shipped to fish blood parasitologists. The author was notified that one of the slides with a blood sample had indeed tested positive for blood parasites.
7. What aspects of the scientific method and scientific collaboration were evident in this article?
The author made many observations such as damselfish were going to cleaning stations, even interrupting their spawning activities to do so, and this process caused them to be away from their territory for extended periods of time. Using the observations, the author formulated questions such as:
- Cleaning stations are used to remove parasites, but what are those parasites?
- How do these parasites affect damselfish behavior?
- Do the gnathiids carry disease? i.e. Do the parasites carry parasites?
Experiments and observational activities were designed to answer these questions. The results were communicated and shared between scientists and as a result, more questions have been generated.
Teaching Phase: How will the teacher present the concept or skill to students?
1. Begin the lesson by asking students to visualize a coral reef. What type of picture is formed?
- Students are likely to mention colorful fishes, corals, and crystal clear blue water.
- Show NSF images or other images or videos of coral reefs. (This 2 minute video from NOAA shows some yellowtail damselfish over damaged staghorn coral at the 28 second mark.)
2. Ask students: What can happen when boats are not careful around coral reefs and how can this affect species like damselfish?
- This 9-minute NOAA video shows the damage caused by boat groundings and the repair efforts done to restore the damage.
- Note: this can decrease the suitability of the habitat for damselfish (fewer places to hide from predators, fewer potential nesting sites, etc.).
3. Ask students: What do you picture when you hear "damselfish?"
- Supply a picture like the one.
4. Ask students: What do you picture when you hear "gnathiidisopod?"
- Supply a picture like the one here.
5. Ask students: What do damselfish need to do to ensure there will be a next generation?
- Students should say the damselfish will need to reproduce. Inform them that damselfish do this by spawning and the male damselfish prepares for the eggs by making a nest.
6. Ask students: What is a parasitic symbiotic relationship?
- Students might reply: A relationship where one species benefits from the association and the other is harmed (although usually not killed).
- Explain to students an organism called a gnathiid isopod parasitizes the damselfish. The gnathiid larva is an external parasite feeding on damselfish blood. The damselfish loses blood and it has to expend extra effort to get cleaned, even during a spawning event.
- Inform students they will be reading the article, "Parasites: Rulers of the Reef," that discusses relationships found in a coral reef ecosystem, including the one between the damselfish and the gnathiid.
Guided Practice: What activities or exercises will the students complete with teacher guidance?
1. Pass out to each student a copy of the article "Parasites: Rulers of the Reef" or make it available to students electronically.
2. For discussion purposes, the teacher may want to have students number each paragraph of the article. If using an electronic copy of the article, students can use a PDF mark-up tool (several tools are available as free downloads).
3. Provide each student with a note-taking guide. Have students complete this guide during or after their first reading of the article. Make sure to provide print or online dictionaries for students to use for the vocabulary section.
- Note: Based on the needs and skills of the students, teachers can decrease the number of academic or domain-specific vocabulary students will define on the note-taking guide.
- For academic vocabulary, students will likely be able to use a variety of vocabulary strategies to define the meaning of the words. For domain-specific (in other words, subject-specific) vocabulary, students will typically need to draw on prior knowledge, use context clues, and/or use a dictionary to define the words.
- Students can work individually, in pairs, or with a small group.
How will you check for student understanding? (Formative Assessment):
1. The teacher can circulate around the room as the note-taking guides are being completed and take note of any specific insights or misconceptions that should be discussed with the whole class.
2. The teacher could also take note of any answers that were not text-based and relied on reader background knowledge.
- Students can present different aspects of their note-taking guides to the class and discussions can be held based on these student responses.
- Open discussion of the note-taking guide will identify depth and breadth of knowledge as well as identify any misconceptions. Teachers can use this sample key to help assess students' answers.
Common errors/misconceptions to anticipate and how to respond:
- Students may have the misconception that parasites will kill the host, but it is usually not the case. Explain if the parasite kills the host, the parasite loses its food source.
- Students may not understand there are ecto- and endoparasites. Explain that ectoparasites are on the outside of the organism while endoparasites are found internally.
- Students may be unfamiliar with the phrases "high-tail it," "cover our bases," "major players," "grist for future research," and "game-changing." Go over these phrases or expressions with students and help them understand what the author means when using these expressions.
Independent Practice: What activities or exercises will students complete to reinforce the concepts and skills developed in the lesson?
Provide each student with a copy of the text-dependent questions to complete. Students should be reminded to continually refer back to the text and to use relevant and specific evidence from the text to support their answers.
Formative assessment can come in the form of the following:
- Teachers can check students' understanding by collecting students' answers to the text-dependent questions, checking their work, providing written feedback, and maybe grading the assignment. Or, teachers can have students share out their responses and the teacher can provide verbal corrective feedback, allowing students to make corrections to their work during the discussion.
Common errors/misconceptions to anticipate and how to respond: Please see the answer key included at the end of the text-dependent questions.
Closure: How will the teacher assist students in organizing the knowledge gained in the lesson?
1. Before the students complete the writing assignment for the summative assessment, review the responses to the text-dependent questions completed earlier by the students. Make sure the misconceptions are corrected and the key points (as found in the sample answer key) are discussed.
2. After students' written responses have been graded and returned with feedback, teachers might wish to use the provided sample response with the class. Students who are struggling writers can benefit greatly from seeing a well-organized, detailed written response. The teacher could show the sample response on an overhead or with an LCD projector and discuss some of the following:
- Have students examine how the topic is introduced in the opening sentences of the introductory paragraph and have them identify the main point of the piece. (Students often struggle with ideas in how to start a written response, and they often want to repeat the prompt back in the first sentence because they are not sure what other options they have. Go over how this writer opened his or her piece of writing. Brainstorm with students other ways the writer could have opened the piece.)
- Have students examine each of the body paragraphs and explain how each supports the main point of the piece.
- Have students identify where the writer effectively uses textual evidence from the article for support of his or her points.
- Have students identify the use of transition words or phrases to make the ideas flow.
- Ask students to identify where domain-specific vocabulary is used accurately and effectively (e.g., damselfish territory, isopods, organisms, parasites, parasitic infestation, gnathiids).
- Have students read the final paragraph to see how the writer wrapped up the piece and connected back to his or her main point established in the introduction.
3. Have students use exit tickets to demonstrate their understanding of the science concepts presented in this article:
- I still have questions about these three science concepts...
- By reading this article I can now prove this scientific point...
- The three most important scientific ideas I gained from this article were...
1. Students will individually respond to the writing prompt. They should be directed to respond with a multi-paragraph response, with a clear introduction, body section, and conclusion. They can refer back to the text as they construct their response.
2. Provide students with a copy of the rubric and go over the rubric with them so they will know how their written response will be assessed.
3. Go over the writing prompt with students and make sure students understand what the prompt is asking them to address.
The prompt: Analyze the article from the perspective of the scientific process that is carried out. Describe the ways in which scientific investigations can be conducted using examples from this text. Where possible, include examples of different phases of scientific investigation: questioning; observing; conducting research; recording, synthesizing, and analyzing the data; collaborating; drawing conclusions; and communicating those results.
4. Teachers will use the rubric to assess students' written responses.
Specific suggestions for conducting the Formative Assessment can be found in the Guided Practice and Independent Practice phases of the lesson.
Feedback to Students
Specific suggestions for providing Feedback to Students can be found in the Guided Practice and Independent Practice phases of the lesson where it says, "Common errors/misconceptions to anticipate and how to respond."