“chemistry is so hard”

“Chemistry is so hard.”

“Did you understand chemistry right away when you first learned it?”

“I don’t understand how you can teach chemistry.”

We just had our Unit 5 test, which was double replacement reactions/solubility, stoichiometry, and equilibrium. It was a long test. Most of my students didn’t finish it. And I heard (for the first time in my teaching career) that students cried after they left my classroom. I let my B day students see their exams yesterday and one student nearly broke into tears at the score. At least one other student refused to even open the exam.

It was admittedly a long exam. And I don’t really like teaching stoich at the end of the year (last year it came during Unit 3, which was the end of first semester). This year, our stoichiometry unit coincided with AP exams (particularly AP US History). My students who aren’t in APUSH had a huge project in their Honors US History class. Adding double replacement reactions and equilibrium to stoichiometry also just made the unit enormous and unwieldy; I’m honestly not sure why we decided to do it this way.

We met yesterday as a chemistry team to rework the curriculum map. I felt really strongly about cutting the units down a bit. A colleague very helpfully put the major topics on small strips of paper and we literally moved them around yesterday.

Overall, I think this sequence will work better. I think it will be better to break things up more. And another colleague yesterday suggested that for sophomore chemistry, maybe we don’t need to layer so many things with stoichiometry. Because the calculations are killer for some of my students. And I have to say, I agree. This unit test left me wondering- why should a student’s math ability dictate whether or not they can pass my class or whether they get a C or a D in my class? Does the ability to solve limiting reactant problems actually demonstrate a deeper understanding of chemistry?

I really liked last semester, because we spent so much time on the particle level and trying to connected it to the macroscale and symbolic (the vertices of Johnstone’s triangle). (I will admit though, I’m a bit ambivalent about teaching electron configuration and the quantum model of the atom. Do they really need that at an introductory level?)  I love Modeling Chemistry because of the emphasis it places on that conceptual understanding, and I’ve been able to convince coworkers to use aspects of it (without necessarily calling it Modeling) in their classrooms too, which is always a win.

I struggle with our curriculum map because it seems so broad. One colleague was advocating for teaching the actual ideal gas law (PV = nRT). In my opinion, that’s often just more math and conversions (convert between bars and atmospheres! Celcius and Kelvin! Torr and atmospheres!) We added in gas relationships this year, which I think was helpful in helping students understand the particle behaviors of gases, and I’m ok with leaving them at that. (We did agree that ideal gas law as the math wasn’t important enough to add back in. Kinetic molecular theory? I’m there, all the way.)

Another colleague really wants to teach electrochemistry because it’s so cool. And yes, it’s cool. It might be nice for students to know how a battery works, but do they really need to know how a battery works? And then, are we expecting them to write half reactions and work with the Nerst equation and all that? Electrochem remains at the end of the year, unless we decide (the following year) to bring it in with reaction types.

There is so much math in chemistry. And I love math, and I think math is beautiful and useful and awesome. But for high school sophomores, I wonder if it’s enough of a cognitive load to try to figure out what’s happening on the molecular/particle level. Trying to also connect that to math adds another layer that causes a lot of struggle for some students, and I don’t know that it’s fair to them.

So here’s the conflict as I see it – either teach less math in chemistry, or teach less content and give them more support to understand the connection between math/symbols, their observations, and what particles are doing that explain all that. I would vote for the latter, but I think the rest  of my course team would find that frustrating. So instead, our curriculum map remains about the same length as always, and we’re usually scrambling to cram everything in (or maybe that’s just me).

It’s a challenge and a struggle. The chemistry class I teach definitely moves at a slower pace than the accelerated course I took as a high school sophomore. And a part of me is sad that they don’t get to see “all” of chemistry, but the rest of me is realistic- when does the calculation of Gibbs Free Energy help in “real life”? I want them to learn how to think critically and learn a bit more about the world around them (we’re made of atoms! How atoms behave explain just about everything if you really want to get into it.), but do they really need the depth that I learned chemistry at in high school?

I don’t want to teach chemistry the way I was taught just because “that’s the way that worked for me, so it must continue to work.” Because it didn’t work for a lot of people. My students went slowly on the unit exam because so many of them were doing all the dimensional analysis as individual proportions. And I’m totally ok with that because it better demonstrates (to me) a conceptual understanding of why they’re doing each step that they’re doing. But those individual calculations are much slower than using a “mole map” or other foldable to figure out the calculations and powering through them. Often adults admit to me that they didn’t really understand why they were doing what they were doing with dimensional analysis until later in college chemistry (if at all). So why do we teach students to blindly follow algorithms that make no sense to them?

I want to challenge my students, I want to show them that the world around them, even things too small to see, are understandable, but I don’t want to set them up for failure (however I might joke with them that my job is to make them miserable). I’m feeling discouraged this weekend because I spent all last week dealing with stressed out students and trying to help them get a last minute understanding of what is happening, and I feel like I failed them on this unit test. Even though I spent the last 7 weeks holding weekly morning review sessions, I had an extra session on limiting reactants during our in-school tutoring time, I posted tons of extra practice, a screencast on how to solve these problems, and all the analogies I could think of with cooking, recipes, etc., on limiting reactant. It was limiting reactant that seemed to be the major stumbling block on this unit exam. Really, I’m just tired and worn out right now.

All of this just leads me to the question (which I’ve had before, but perhaps not articulated in this space) of why do we teach high school chemistry? A friend (who is not an educator) was genuinely wondering if it would be better to find out what students are really passionate about and then let their high school experience be more focused, rather than forcing students to sit through prescribed subjects that they don’t care about. He spoke from his own experience, where sitting through calculus was not really useful or productive for him. While I think there’s some problems with pushing kids to find a “passion” (as better articulated by this NYTimes blog post on passion in kids), I do wonder about the potential for real vocational education. I can see value in educating students with real life skills and for specialized professions that don’t need a liberal arts college degree, but I worry that it will result in more tracking and more segregation/stratification in society.

Some of my colleagues justify curricular and instructional decisions “because that’s what they need for college.” Why is that an appropriate reason to teach what we teach and the way that we teach it? Do my students really need to know the quantum mechanical model of the atom and how to write out an electron configuration? True, there are places where concepts I learned in chemistry are useful in every day life. Dimensional analysis and conversions are actually incredibly practically useful, but it’s the conceptual understanding that’s helped me more than memorizing how to set up a problem. So really, a deeper conceptual understanding is (in my opinion) better than just memorizing a bunch of algorithms and formulas, but the students want me to teach them THE method to solve the problem. It takes much longer to develop a deeper conceptual understanding of what’s happening, and I would love to take the time, instead of rushing through the content and feeling like I’ve failed my students because they tanked the unit exam.

I wish that I had time for some deeper conversations with colleagues abut why we teach what we teach, but most days there’s barely enough time to discuss what’s happening that day or what happened yesterday. So instead, I’ll just leave this braindump here. If anyone has suggestions, ideas, comments- please, let’s start a conversation.


Year 3- Tweaking

Classes start tomorrow, “officially” launching my third year teaching. While I find myself with some anxiety about tomorrow (did I plan everything? Do I have enough time for what I want to do? Or not enough time? Did I get all my materials? Did I forget to copy something? How do I pronounce their names?), overall I’m looking forward to this school year. This is the first year I’ve been able to focus on a course that I already taught once, so I get the chance to tweak things, which is exciting.

Some things that I’m trying/tweaking:

  • Group roles (again). I tried these last year with the suggested POGIL roles, didn’t really go over well. Possibly because I didn’t support/enforce roles as much as I should have. And then I tried again with some modified roles, and same thing. This time, I pulled the roles and descriptors from some of the mathematics Complex Instruction work (“Strength in Numbers: Collaborative Learning in Secondary Mathematics”) and am planning on taking some time during the first few days for students to look at their roles and examine what kind of leadership each role requires. Of course, it helps that this year I was able to think about roles and rework what I wanted to do with these before classes actually started…
  • Pseudo-standards based grading. My school is not an SBG school, though the entire junior biology team has gone SBG. But an idea I got from another teacher this summer was spiraling quizzes– where topics stay on the quiz for 3 weeks (they give a weekly Friday quiz) and this gives students a chance to show improvement/mastery. Going to try this with chemistry. I reworked our gigantic curriculum map so that each unit has 5-7 “big” standards with each objective on the curriculum map as a “sub” standard (really, is there better vocabulary for this? Because I haven’t figured it out.) And each “big” standard is hopefully going to be a focus on each quiz, with quizzes ranging from 5-15 points. Full discloser: this is totally experimental. But what I found in the past two years is that the students don’t really notice that I’m trying experimental things on them. Or if they do, they don’t find it unusual. Not sure if that’s a byproduct of the new initiative/testing environment that they’ve spend their entire school careers in, or if my student population gives teachers the benefit of the doubt, but I’ll take it.
  • Interactive(ish) notebooksI loved the idea of interactive science notebooks, but couldn’t really justify the “only write input on the right side page” part. And maybe the problem was I wasn’t giving students enough direction on how to process on the left side page. So I’m changing it to one left-side page for each day is devoted to some processing/reflection and the rest is for their daily work. (I stopped making individual copies of handouts and made them write everything in their notebook last year. Saved tons of paper, but perhaps not ideal in terms of giving students something to use in studying… Still thinking about how to help them with making their work/notes useful…)
  • Google classroom. Last year, I used Doctopus & Goobric to have students submit lab reports. And then my district rolled out Google classroom for everyone, so trying it out. I’m already seeing the “scroll of death” as one teacher called it, in the main page for each class (when there are only 3 announcements/assignments listed so far!) but my school’s homework site was also just a “scroll of death” with assignments, so I suppose it’s not that different.

And then, as last year, I’m incorporating POGILs (modified, sometimes taking out some of their paper-based models and replacing with a hands-on model) and Chemistry Modeling Instruction and other random things to get at content. (By the way, I’m really sad that chemthink.com seems to be down, possibly long-term. If anyone has another, similar resource, I’d love to hear about it.) This year I also want to see how the structures I put into place help students really interact with the content. How do I support groupwork to help their groups function well, and how do I help students see learning as a progression?

Hopefully I’ll remember to take the time during the year to actually reflect and post here about how things are going…

Chemistry modeling: a recap

I just finished a two-week workshop on Chemistry Modeling. For those of you who aren’t familiar with the modeling methodology, I highly suggest checking out the American Modeling Teachers Association (AMTA). These are some of my thoughts and reflections on this workshop and the chemistry modeling curriculum as a whole.

This workshop was a good introduction to both the modeling methodology and the chemistry modeling curriculum. The chemistry modeling curriculum is fairly recent compared to the physics modeling curriculum, so most of the teachers who are currently using this curriculum haven’t been using it long, but it was great to hear from different teachers who are using this methodology in their different classrooms.

The modeling chemistry curriculum focuses heavily on the particulate nature of matter and introduces kinetic molecular theory in Unit 2. I am still contemplating how this curriculum compares to a more ‘traditional’ chemistry curriculum. Primarily, the amount of content covered is significantly less, but that is true of the physics modeling curriculum as well as any curriculum that is heavily student-centered and based in student inquiry. Additionally, because the chemistry modeling curriculum considers chemistry from a historical view, students are presented with models that must be refined and rethought throughout the year. This results in students using the Thompson model of the atom (‘plum pudding’) for most of the year, as the Bohr model is not necessary to understand and explain the observed phenomena until periodic trends are discussed (also at the end of the year). I’m still considering whether I’m ok with students holding a ‘wrong’ model of the atom for the majority of the year. However, I do like the sequencing of the curriculum because it follows a more logical progression and the topics do build upon each other. The consistent use of particle diagrams would also allow students to connect the macroscale phenomena and symbolic representations with what is occurring on the microscale. After many discussions with fellow chemistry teachers on the ‘triangle’ of chemistry (first proposed by A.H. Johnstone, I believe), I feel like the modeling curriculum will allow students to gain better conceptual understandings of chemistry.

For me, a key take away from this workshop may not be directly tied to the modeling curriculum. The presenters emphasized the use of ‘for every’ language vs. ‘per’ when discussing slopes and ratios. (This idea was from Gary Abud’s presentation at ChemEd in 2011; he has a nice recap on his own blog.) They also pointed out the value of allowing students to use proportional reasoning rather than dimensional analysis in solving problems. Students in high school are often still concrete thinkers, so proportional reasoning makes sense to them whereas dimensional analysis and t-charts may simply be algorithms they use without understanding the concepts. The modeling curriculum uses IFE (Initial/Final/Effect) and BCA (Before/Change/After) tables for gas laws and stoichiometry, respectively, to promote students’ conceptual understanding rather than giving them equations and algorithms that they can use without ever understanding the chemistry. Students can solve gas law and stoichiometry problems without ever being given the ‘official’ gas laws (Boyles’, Charles’, Gay-Lussac’s) or t-charts for gram-gram conversions. These are all aspects of the modeling curriculum that could be used without fully implementing this curriculum. And of course, I see no reason to limit the use of ‘for every’ language to chemistry.

However, several presenters and teachers who have implemented the modeling curriculum piece-meal highly recommended going “all in” if possible. They suggested this simply because it can take the entire year to build the classroom community that is necessary for successful modeling, as so much depends on the Socratic discussions and whiteboard presentations. I would agree that if whiteboarding is going to be a part of the class, it must be interwoven throughout the year. However, some of the activities and strategies could still be used in a more traditional sequence of chemistry. Additionally, many of the labs and activities in the ASU curriculum are currently used by chemistry teachers regardless of their curriculum and/or could be swapped for activities that are currently used. The presenters pointed out specific units that were more conducive to using whatever materials teachers were currently using (e.g., the mole and stoichiometry were two units where they suggested that current materials could be easily modified for a modeling classroom).

During the workshop, we were able to talk to a panel of students who had gone through a year of modeling (either chemistry or physics). This gave me a good idea of how students view modeling, and overall the feedback was very positive. However, most of the panelists were students who enjoyed science and were A-B students. One student who does not consider herself as ‘good’ in science stated that while she didn’t feel like she fully understood chemistry (as in being able to do all the calculations), she felt like she got the concepts. I think she felt like this was a detriment to the modeling curriculum (as she wasn’t able to fully understand the quantitative side of chemistry), but as teachers, we felt like we would be very successful if all of our students were able to get at least a qualitative, conceptual understanding of chemistry. I would have appreciated hearing from students who were in the ‘regular’ track (all of the students were from the ‘advanced’ courses), but these students gave me an idea of how students view modeling compared to their previous science classes. In particular, students in chemistry stated that they enjoyed modeling compared to their biology classes because it was less memorization.

The modeling curriculum also tries to connect energy throughout the chemistry curriculum rather than treating phase change and enthalpy as disparate occurrences. They also encouraged changing the wording used with students to emphasize that energy is the same, it is simply stored in different ‘accounts’. This workshop clarified the modeling worksheet that we analyzed as a data source for our CI in the spring. The modeling curriculum, as a first-year chemistry curriculum, does not consider phase changes when considering energy in chemical reactions to simplify the picture for students. As chemistry teachers, we had many interesting discussions on how to represent energy in the chemical systems using the LOL charts in the modeling curriculum. It was difficult to explain reactions that are rather complex because entropy and enthalpy must both be considered in the energy discussion, and we discussed whether it would be best to leave these reactions out of the curriculum altogether to avoid confusion. I really enjoyed these discussions because they forced us to consider the rationale behind the decisions to include or exclude certain topics in the modeling curriculum. However, the idea of conservation of energy is introduced early (at the point of phase changes) and used in all energy discussions, and I absolutely loved that.

I would love to use this curriculum and see first-hand how students respond to it; however, I won’t be teaching chemistry next year (I signed up for this PD before I started interviewing for jobs). Nevertheless, I will be teaching physics using the modeling curriculum, and the experience with working with this curriculum both as a student and as a teacher will be valuable for my first year of teaching. Additionally, I was able to sit in on the physics workshop for one day, and see some of the similarities and differences between the physics curriculum and the chemistry curriculum. (One major difference was that the physics units all appear to be structured similarly- paradigm lab, model development, model deployment, lab practicum- whereas all of the chemistry units do not involve developing a mathematical model and therefore are structured differently). I also think that the discussions about the use of algorithms vs. promoting student understanding of the content will be important to keep in mind as I teach freshmen who are used to high levels of academic success. I am very excited about trying to use ‘for every’ language rather than ‘per’ for slopes and other proportional relationships (e.g., ‘for every 1 cm3 of water, there is 1 g of water’ rather than ‘water has a density of 1 g/cm3), and I am sure that this has a place in physics as well as in chemistry. The different whiteboarding techniques that were discussed will also be something that I can draw upon in my teaching for next year (groups, individuals, choosing who presents, gallery walks, etc.).

However, a major lingering question that I had after this workshop was how/when to incorporate ‘real life’ into modeling. The chemistry modeling curriculum did not seem to really tie the chemistry back to what students encounter on a day-to-day basis, and therefore I think it would be difficult to get buy-in from students who are typically disengaged from school in general. I wonder if the physics curriculum is similarly distanced. Science is applicable to our students’ everyday lives in a myriad of different ways, but many students see science as something that is ‘other’ from them. The lack of student buy-in could kill implementation of this curriculum. The modeling curriculum presents chemistry in a way that I can really appreciate as a teacher, but how would students who are disengaged from school see this approach?