Making Observations Like a Scientist
Catherine Rohrbaugh teaches students how to take notes and analyze text across different content areas to foster independent learning.
Teacher: Catherine Rohrbaugh
School: Dillard Drive Middle School, Raleigh, NC
Lesson Topic: Creating a wet-mount slide
Lesson Month: November
Number of Students: 28
Featured Lesson’s Student Goals:
- Content objectives – Create a wet-mount slide to view under different objective powers using a microscope
- Literacy/language objectives – Use scientific language like a scientist (naming parts of microscope); build graphic literacy skills (microscope diagram); connect reading with the physical world (connecting microscope part names to functions, i.e., what it looks like on the page with what it looks like in front of them: tactile recognition); follow multistep directions; build visual literacy (drawing what you see); be able to follow a list of procedures
Common Core State Standards for English Language Arts & Literacy in History/Social Studies, Science, and Technical Subjects
Follow precisely a multistep procedure when carrying out experiments, taking measurements, or performing technical tasks.
Throughout this 26-day unit—Cells: The Microscopic World—students used microscopes to look at single-celled organisms. It was the second unit of the school year and the students' first exposure to exploring things on a microscale (following a unit on weather, which was on a macroscale). The lesson on creating a wet-mount slide was the first of the unit. It was an introduction to the idea of something small. The purpose of the lesson was to teach students how to use a microscope so that they could examine cells. After learning about animal and plant cells, students moved on to a new unit focused on the human body, where they learned how individual cells have their own “jobs” that collectively make up the different parts of the body (e.g., cells make tissues, tissues make organs, organs make organ systems).
Before the Video
This was the first lesson of the unit. Before this lesson, students had studied the different parts of the microscope on paper but had no hands-on experience.
During the Video
Ms. Rohrbaugh began by reviewing the parts of the microscope with students, encouraging them to touch each component as it was named. She then engaged students in a discussion about scientific thinking in the 1600s and how it differed from modern scientific thinking (linking it to the idea that scientists continuously question things). Students independently read a short article on the same topic as background information and used close reading techniques to annotate. Ms. Rohrbaugh asked students to write two statements: “I wonder what…” and “I wonder why…” to drive home the concept of asking questions in science.
Then, to show the importance of gathering evidence, Ms. Rohrbaugh led students in a microscope activity: creating a wet-mount slide of a piece of paper with the letter “r” written on it. She first modeled the activity, and then students worked through the lab in pairs by following a checklist of procedures. Ms. Rohrbaugh provided a “foldable” lab sheet as an interactive component to the lab. (Students folded back the pages to reveal only some text at a time and drew what they saw under the microscope.)
After the Video
Following this lesson, students made and examined wet-mount slides of plants and single-celled organisms.
To prepare for this lesson, Ms. Rohrbaugh created the lab and set up the microscopes, slides, and covers.
Students did not need any prior knowledge or comprehension skills to participate in this lesson.
Ms. Rohrbaugh had students use close reading strategies for the assigned reading (such as using colored pens to visually identify different text components and aligning like text features in margins). She asked students to touch each piece of the microscope as they were reviewing its parts to help with tactile recognition. Ms. Rohrbaugh modeled the wet-mount slide activity and used a projector for greater visibility. She designed the pages of the lab worksheet with especially large margins in order to encourage more annotating by students; employed a “foldable” design so that students were presented with a small amount of new information at a time; and created a checklist of the procedure so that students mark off each step as they completed it, one by one. When students struggled to make connections, she related concepts to real-world applications (such as connecting the upside down “r” to the appearance of letters on clothing in a mirror).
Throughout the year, Ms. Rohrbaugh focused on organization for students. She used a table of contents system in which every piece of paper handed out during the school year was numbered; students kept each page in numerical order in a notebook for easy reference and access. Ms. Rohrbaugh offered her notes to students ahead of time so that they could print them out before class if they chose, and always set expectations for students at the beginning of a lesson. As much as possible, Ms. Rohrbaugh incorporated movement into activities to keep energy levels up and reach kinesthetic learners.
Students sat four to each table and worked in pairs (either with the person across or next to them). Ms. Rohrbach scaffolded the groups so that the stronger students sat at diagonals to each other (and the less strong students at opposite diagonals); thus, each pair always included one strong and one less-strong student.
To facilitate full-class discussions throughout the year, Ms. Rohrbaugh had students first write their answers to posed questions on paper, talk them over with a partner (to gain confidence), and finally share them aloud with the rest of the class. She also focused on building a rapport with students that fostered a supportive environment where students were not afraid to take chances.
Resources and Tools
- “A Closer Look” lab sheet with diagram reading, “foldable,” and procedure checklist
- Lab materials
- ELMO (visual presenter)
- Colored pens
- Class website
Ms. Rohrbaugh gauged student understanding with spontaneous questions that students answered in a “live poll” using SMART response system technology (students’ responses were anonymous to others students but could be tracked by Ms. Rohrbaugh; the results appeared as a graph on the projector). She also used a “sticky note quiz” in which students quickly ask her a question about something they are learning. (If a student had a hard time coming up with a question, he or she likely did not understand the content.)
At the beginning of class, Ms. Rohrbaugh presented the lesson’s objectives to students (based on standards but in her own words); at the end of class, she asked if they felt they met the objective. Students also used a checklist to progress through the steps of the microscope lab.
Students had to show Ms. Rohrbaugh that they could prepare a wet-mount slide and then use a microscope to properly focus the letter “r.” Later in the unit, students were tested on their ability to recognize the difference between plant and animal cells under a microscope.
Ms. Rohrbaugh used pop notebook quizzes to keep students organized and using the table of contents system (e.g., “Turn to page 3 and tell me what the first question is.”). She also did weekly prefix and suffix quizzes in which students were quizzed on five content-related prefix or suffix words.
Impact of Assessment
Ms. Rohrbaugh’s students had varying degrees of understanding after the lesson. Based on her assessments, she addressed some misunderstandings the next time the class met (including naming more parts of the microscope, encouraging more use of vocabulary, reviewing the wording of a written question, and stepping back more often to encourage self-reliance to find answers).