DNA Discoveries: How Did We Get From There to Here? (Day 4 of 4)
Lesson 4 of 22
Objective: SWBAT trace the evolution of scientific thought and research into the structure of DNA.
This four day lesson series gives students the opportunity to follow the flow of scientific discoveries that led to an understanding of the structure and function of DNA. I have used a jigsaw method to introduce this material for many years and this year I added an additional day using an effective and engaging drama technique to give students the chance to hear each other's versions of the science discovery stories, check for understanding, and be active listeners and participants in their own metacognitive processes.
On Day 2, students meet in their expert groups to compare notes and prepare to present their findings to their lab group. Standard(s): W.9-10.2d, SL.9-10.1, SL.9-10.1a, RST.9-10.2, RST.9-10.4, HS-LS3-1, XC-SF-HS-2
And finally, on Day 4, students participate in a drama technique activity to share out individual interpretations of the DNA discoveries while in the roles of the actual scientists and reporters tasked with interviewing them. Standard(s): W.9-10.2d, SL.9-10.1, SL.9-10.1a, SL.9-10.1b, SL.9-10.4, HS-LS3-1, XC-SF-HS-2
This last day is what makes this lesson series really shine! Students enjoy the role playing activity and are able to clearly assess and communicate the learning benefits they saw in both of their researcher and reporter roles. I can't wait to hear about your experience using this teaching strategy with your students!
1. Ask students to assist you in arranging the chairs of your space into two circles facing each other.
- Note: I used our library space but also considered doing this outside, anything to get us out of our normal environment and set the stage for something new and interesting. The key is to have the chairs facing each other in pairs. The physical space for this activity matters so that students can interact easily and to reduce transition times as students move around the circle.
2. Tell students to pick a seat and to take out a piece of paper and their DNA discovery chart document and/or notes from our jigsaw activity.
3. Tell students that today they will be playing the roles of their different expert group scientists and reporters. Tell the inside circle that they will be their scientist (Griffith, Avery, Hershey & Chase, or Watson & Crick/Chargaff/Franklin. The outside circle will be reporters. Each time you call switch, the scientists will stay seated while the reporters move over one chair clockwise and then they will repeat the process.
4. Ask students to take a moment and write down either a brief paragraph monologue/summary of their work (scientists) or their name/news organization/general questions they could ask (reporters). Allow for a few minutes of quiet time while students think and write. Tell them they will be leaving this paper with you as they leave just for you to see their thinking. As you can see from the photo above, students will use the brief time you give them to prepare for this new activity. Check out the following two samples of student writing during this preparation step. Both samples show both a short set of questions they can ask in the reporter role and a brief summary of their DNA discovery experiment when they shifted roles mid-way through the activity.
- Note: if you find that students need support with this step, you can refer to the Powerpoint slide presentation for additional information.
5. Tell students that they do not have to take notes on their discussion unless they will find it helpful as they complete their DNA discovery chart assignment due next week. The primary focus here is on listening and speaking.
1. When students are ready, have them begin. Be sure to tell reporters to introduce themselves! This helps to get them into character.
2. Call switch when you hear conversations winding down. For some classes, this may be only a minute while for others, they will be able to sustain a longer conversation. My goal was to keep the energy and discussion flowing and I adjusted my timeframe to that end.
3. After about 5-8 minutes of switching, ask students to stand up and trade places so that the students who were sitting in the inside circle (scientists) move to the outside circle (reporters) and vice versa.
Check out some pictures of my students at work! As you can see, student scientists are highly engaged in the activity, grabbing nearby models to illustrate their point and gesturing as their reporter partners actively listen for information and to help frame their next question.
4. Explain to students that they will now have the chance to experience the other role (scientist or reporter). Ask them to take a minute to either write down a paragraph of what they might say about their research (scientist) or questions they could ask (reporter).
5. Begin the process again for another 5-8 minutes.
- Note: I did not encounter any engagement or off task behavior issues during this active session. I attribute this to the fact that there was so much movement thoughout the activity and that the overall task was new, engaging, and required focus and active participation within each pair conversation. The few times I saw two friends sitting near each other that seemed to be distracted from their task, I simply reminded the group that their goal was to focus solely on their reporter/researcher conversation and that seemed to do the trick. I think in the future, I could make sure that close friends who struggle in terms of attention span do not take seats around the circle directly next to each other.
1. Ask students to locate their original lab groups and to move so that each lab group is sitting in the circle next to each other.
2. Once students have rearranged themselves to be in their groups, ask them to discuss two prompts:
What was this process like for you?
What did you learn?
3. Using the spokesperson protocol, have student groups share out their conversations. You can also ask probing questions such as: which role did you like better (reporter or researcher) and why? What are some challenges you faced and how did you deal with them?
- Note: You will get all kinds of great answers! Equal numbers of students liked being both roles: reporters liked hearing about all of the experiments and checking their understanding while scientists liked the task of really knowing their experiment really, really well. Both groups liked the listening, moving, and interacting piece of this activity and some students really got into the role playing component of the work, which made it especially engaging and enjoyable for all of us. One student commented that sometimes they weren't sure if their scientist said the right thing, which was a perfect time for me to transition to our next segment of this lesson!
Here is a video clip of one student spokesperson responding to our prompts.
1. Ask students to discuss in their groups one essential question that they feel they need to ask for more support, clarification, or specific detailed aspects of the science discoveries we studied this week.
2. Use the spokesperson protocol for sharing out responses. Typical topics you may encounter that could require your input/reteaching:
- The idea of a transforming factor--why is Griffith included in this set of DNA experiments since he didn't know anything about DNA? (Even though we didn't know it was DNA at the time, Griffith discovered something that set up the next set of questions for scientists to research that eventually led to where we are now)
- Chargaff--how is his work related to the base pair rule? (This is another scientist who added to our knowledge about DNA although he was not necessarily attempting to do that exactly. Although he did not coin the term 'base pair rule,' because his work was influential in determining it, he is assigned some credit)
- Hershey and Chase--what is radioactive labeling and how did it help them figure out DNA was the genetic material? (Switching from 'radioactive' labeling to 'color' labeling in drawings tends to help students get what was going on at the molecular level and how exactly the researchers could track the proteins and nucleic acids in their experiment. Also, mentioning current medical procedures like barium tracers is helpful--many students will know what those are due to a relative's experience as a test for a medical issue)
- Watson and Crick--what was their experimental procedure? (Although this will come up, other students will be able to fill in the answer for the class if you ask for help here. Students will understand that the duo didn't do any experimental work themselves but instead combined the data derived from the work done by other researchers in order to create an accurate representation of the DNA molecule).
3. Remind students to leave you their reporter/researcher prep notes and field any additional questions about their written DNA discoveries chart assignment.