As the students enter the room, they take out their journals and respond to the prompt:
What is one question that you have about the brain? How could you find the answer? Do you think scientists know the answer?
While the students work on responding to the prompt, I circulate through the room reading their responses and offering help. Some of the students have difficulty responding to the prompt because they cannot think of questions. I try to assist these students by providing sentence stems such as, How does __________? Where is _________? How do we know ___________? I also ask some of them to refer back to their notes to see if there is something they would like to know more information or details about.
Once the students have had an opportunity to write, I ask for volunteers to share their questions. I am careful to point out that they are not expected to know the answers to the questions and that I will not be answering the questions as they ask them. If students do not volunteer, I draw cards with the students' names on them. As a student shares their question, I ask him/her if he/she has any suggestions for how we could find the answer. The other students in the class are welcome to answer this question as well. I also ask the students if they think that scientists know the answer to the question. The purpose of this discussion is to begin to get students to think more actively about the information that we are learning as well as provide practice in developing scientific questions. In a later lesson, I will have the students select some of their questions to research.
This is the video students view prior to this lesson.
This is the Brain notes review that the students turn in prior to this class. This student notes review is an example of proficient work on this assignment. Several students missed the last question on the assignment because they did not compare and contrast the information. When we review the notes in class, I focus on this question with the students and they are able to correct their work as necessary.
As I review the notes with the students, I use various models and books to demonstrate information. For instance, our school library has two copies of the Phineas Gage biography and I share pictures and information from this book during our review of the notes. I also use the Seymour Simon book Brain to show the students various pictures of the brain.
Reviewing this set of notes addresses NGSS MS-LS1-2 and MS-LS1-8 as we discuss the different structures of the brain and their functions.
While reviewing the student's notes reviews about the brain notes, I notice that some students record different responses for the number of neurons in the brain. These numbers range from 86 billion to 200 billion. I see these differences in numbers as an opportunity for the students to explore more about scientific research studies. In order to prepare for this portion of the lesson, I located various research studies. I also used a chocolate mold to make brains out of chocolate. Before the chocolate hardened, I mixed in numerous cake sprinkles, being sure not to distribute them evenly.
I began this section of the lesson by giving each group of students a chocolate brain* and telling them that the sprinkles in the brain represent neurons. I then ask them to devise a method for determining how many neurons (sprinkles) are in the brain.
Students work in partnerships to come to a consensus on the method they would use to determine the number of sprinkles. They are expected to be prepared to share that information with the rest of the class. As the partners discuss their thoughts, I move from group to group, listening to their ideas and asking them to provide more details about their thoughts. Once the partners have an opportunity to develop consensus, I ask them to share their thoughts with the class. I begin by asking them if they think it is possible to count all of the sprinkles and if they think all of the brains had the same number of sprinkles. The students mention that it is difficult to count the sprinkles and many of them decide that the best way to try to determine the number of sprinkles is to count them in certain sections and then use math to determine the overall number. This portion of the activity requires students to think about topics related to NGSS SP6 (Constructing Explanations) and SP5 (Using Mathematics and Computational Thinking) in addition to Crosscutting Concept Structure and Function, specifically:
I ask students how they think scientists determine the number. I explain that I will give each group of students an article to read, along with the following questions about the article: Is the source reliable? How do you know? How many neurons does the article state there are in the brain? How did scientists arrive at that number?
These are the articles I share with the students:
While the students read through the articles, I circulate through the room, helping them as necessary. I also ask each group whether or not they think their source is reliable and to explain why. After providing sufficient time, I call the class back together and have each group share their answers to the questions with the rest of the class.
Having the students read through various texts addresses CCSS RST6-8.2 (determine central ideas of texts) and RST6-8.8 (distinguish among facts and reasoned judgement based on research findings). As they read and discuss, the students also address NGSS cross cutting concept Systems and System Models (Models are limited in that they only represent certain aspects of the system under study) as they discover that the models are limited.
* Brain molds can be found online, or in stores that sell baking supplies.
After each of the groups have had a chance to share their findings, I ask the students to summarize the activity and to suggestion how scientists have come up with different numbers. The students are able to articulate that the scientists used different methods to determine the numbers and that the numbers are approximations. Since this unit is the beginning of our explorations into anatomy, it is important for the students to understand that human bodies are not exact replicas of the models that we examine in class.