Isobar & Isotherm Lab
Lesson 13 of 17
Objective: SWBAT define an isotherm and create and interpret an isotherm and isobar map
This lesson is a fairly comprehensive lab which gives basic information and then asks students to assemble both isobars and isotherms as a result. After a brief laboratory introduction and some covering of basic vocabulary (as well as a few key "rules" which dictate how isobars should be constructed) students jump right into building both an isotherm map (which is simpler), which is then followed by a slightly more complex isobar map. They finish the lab with a very basic analysis and a few Regents-based question before ending for the day!
As a note, there are no special materials or equipment needed for this lab. If you plan on doing the supplementary computer portion (see Analysis section below, you may need at least one computer per two people).
[Note: For embedded comments, checks for understanding (CFUs), and key additional information on transitions and key parts of the lesson not necessarily included in the below narrative, please go to the comments in the following document: 5.13 - Isotherm & Isobars (Whole Lesson w/comments). Additionally, if you would like all of the resources together in a PDF document, that can be accessed as a complete resource here: 5.13 - Isotherm & Isobars (Whole Lesson)[PDF]. Finally, students may need their Earth Science Reference Tables [ESRT] for parts of the lesson (a document used widely in the New York State Earth Science Regents course) as well.]
Do Now & Objective(s)
Students come in silently and complete the (attached) Do Now. In this case, the Do Now is a review of material that students need additional help on from this unit, and is extended into two pages to allow students to see the images clearly and easily (as seen in most of my alternate lessons, most of my Do Nows are only one page). After time expires (anywhere from 2-4 minutes depending on the type of Do Now and number of questions), we collectively go over the responses (usually involving a series of cold calls and/or volunteers), before I call on a student and ask them to read the objective out loud to start the lesson.
As a general note, the Do Now serves a few purposes:
- It serves as a general review of the previous day's material;
- It is a re-activation of student knowledge to get them back into "student mode" and get them thinking about science after transitioning from another content area or alternate class;
- as a strategy for reviewing material students have struggled with (for example, using this as a focused review for material that they have struggled with on unit assessments or recent quizzes); and,
- It is an efficient and established routine for entering the classroom that is repeated each day with fidelity (I never let students enter the classroom talking. While it may seem potentially severe to have students enter silently each day, this is both a school wide expectation and a key component of my classroom. In many respects, I find that students readily enjoy the focus that starting with a quiet classrooms brings each day).
Introduction & Vocabulary
This section is intended to be very brief, but it is arguably the most critical part of the entire lesson, as failure to adhere to some of the basic rules that they learn in this section will mean completely incorrect isoline map construction techniques. We start at the top of the Introduction & Vocabulary resource, where I have students read out the rules one-by-one. After we read Rule #3, I turn student's attention to the isobar map in the middle of the page, where I give them 10-20 seconds to draw the 10 degree isotherm. I then confirm this by drawing my isoline on the ELMO, being clear as I'm doing it how I'm connecting the points, not going outside of my associated value.
I then ask them to do the same thing for the 15 degree isotherm, but usually purposefully make a mistake by stopping the isoline before it reaches the end of the map. I then ask what I did wrong (refer them to the "rules" if they needy help), and usually get told that I need to fully extend the isobar to the end. Have students replicate the isotherm on their own laboratory sheets.
We then read the remaining rules, and then I have students draw the 20 and 25-degree isotherms, after which they confirm with a partner and check their work on the provided teacher key (which I display on the ELMO).
The final step of the process involves important vocabulary words, which I ask the students for help in defining. The embedded notes in the connected Word document above indicate that I give students the first definition and then ask them to come up with the other two, but in execution, I found that by this point the students could more or less define all three terms with little assistance. When I put it to the group ("who can define isoline"), there are numerous hands in the air to answer.
Isobar & Isotherm Map
Before the next section starts, I have students transition into the laboratory groups. As noted in my other traditional "lab days," I teach in a normal classroom. Students have paired desks (they sit two to a larger desk), but that still necessitates that they combine desks to form their lab groups of four (4) students. So, in order to do that, I have the students rearrange the desk order into "lab tables" of two desks. This creates a pretty fair representation of larger lab groups in my classroom, and, like most things, this process is timed. As of now, two of my classes have done this entire transition (I stop the timer when everyone is seated) in six seconds!
Anyway, once that transition is complete, I ask that they begin with the isotherm map on the second page of the Isobar & Isotherm Map resource, both following the rules (in the previous section) and the directions on the first page of the Isobar & Isotherm Map. Usually, after circulating a few times just to make sure all groups are on task, have their materials ready, and are working diligently together, I'll do a quick check of the first one or two isotherms on the ELMO with them, just to ensure they're on the right track. I wanted to post a few pictures of student work so you can see their progress here: Student Work Sample I, Isobar Map Sample, & Constructing Isobar Maps
Common student problems:
- Not going to the end of the isoline map
- Making isolines where there are none
- Crossing or connecting isolines
- Not making a 70 degree isotherm on the first map
- Not using their notes! (You can see two videos below, one of me helping my students, and the other of them reading through the directions on their own: Helping Students Work Through A Problem & Reading Isotherm Directions)
I find that these are the five biggest mistakes to be wary of. In particular, I found most students didn't make a 70 degree isotherm, even though they noticed a 71 degree point on the map. I inform them that as the rules indicate, you should go up in the same interval (in this case, the interval is 10 degrees) until you have no values that reach the higher interval (again, I stop at 70 because there are no points on the isotherm map that are higher than 80 degrees).
Once student groups are finished with the isotherm map, they're allowed to immediately transition into the more challenging Isobar map on the last page of the attached resource.
Post-lab, students are asked to jump right in to the attached Analysis section after their lab is complete (you can see a video of me asking one of my students about the Analysis section in the Analysis Student Clip video attached). The first six (6) questions are fairly straightforward in that they ask students some basic questions that analyze and interpret information contained in their created isotherm/isobar maps. Once they finish that section, assuming they have time available, I have them skip the computer-based portion and jump right into the Practice section, which begins after the Analysis section is complete (I let my students work together on this section as long as they're in laboratory groups). You should note that the attached Practice resource is the same as the Rubric & Homework in the bottom Closing section, but should definitely be started if students have time available. Additionally, as will be noted in the next section, anything not done is meant and intended to be completed for homework at home.
[Note: There is an associated website that students can go to if they finish both the Analysis and Practice/Homework section, but I definitely should note that it isn't something your groups could do in one day, unless you have significantly longer than one hour. I'm leaving the website in the resource because it may be helpful for you, or you may (as I do) have some really advanced groups that work well together and have extra time. Similarly, and I've also done this in the past, it may be helpful to spend an extra day on the material and have them go to that website (link can be found here) - it really is a cool website that lets them practice and check their work with isotherms.]
Unlike most of my other lessons, there is no exit ticket associated with this lesson. In the last few minutes of class, I definitely want to have the room ready for either my next period, or an alternate class that might be using the room (I share a room with another science teacher, which makes clean up all the more important at the end of the period).
I generally say this in all my lab-based lessons, but I think it's always important to: 1.) save more time than you think you need and 2.) have a hard stop at the end of a lab. Once that time is reached, no lab (or computer work, if they are out) should continue. If you're a student in the room, you immediately have to begin the process of cleaning up your work space (and if necessary, shutting down your computer). Since, as mentioned above, I also share a classroom, I also give them some time to make sure they're all prepared for transitioning out of the room. Students are also asked to make sure they have the associated Rubric & Homework (the same document in the previous section) to complete if their group did not yet get the chance to do so.
In the last minute or so, I utilize the same procedure I do on non-lab days, which is to ask the students time to think about their self-mastery of the objective (which is posted on the whiteboard), through some guided questions:
- Do you feel that you mastered the objective for the day?
- Can you reiterate one thing you learned about ____________ (in this case, something like "How did the isobar/isotherm creation process go?" or a procedural question like "How was it working together today?", etc.)
Once I take 2-3 individual responses (sometimes I'll ask for a binary "thumbs up/thumbs down" or something similar), I have students leave once the bell rings.