"Unit 8" and venting

I haven't had a lot to update lately because we've been in a furiously of trying to cover the standards before the EOC.

Last week, we did do the Describing Chemical Reactions Lab in Unit 7.  It's a good lab.  It went well.  I took zero pictures.

We sadly got to spend only a block and a half of on stoichiometry.  It wasn't enough, but we have so much more to cover.

We have now entered "Unit 8" which is not the same as Unit 8 in the modeling curriculum.  I've had to create "Unit 8- Models of the Atom" myself for all of those hodge podge of standards that we have yet to cover-- namely protons, neutrons, and electrons.  And unfortunately, we have zero time for inquiry.  It's been a hellacious week of direct teaching so far.  Yesterday we got through Rutherford and Bohr, with drawing Bohr models and determining valence electrons from the Bohr model.  Today, we learned Lewis diagrams and isotopes.  Tomorrow we'll finish up isotopes by talking about nuclear reactions (a HUGE chunk of standards for my state).  Thursday we'll do the quantum model of the atom and e-config (not.enough.time).  Friday we will begin practice testing/review.  Mon-Wed next week will be review days, although I am not guaranteed to that I will see all my students every day because of their other EOCs.  Thursday is our EOC.

Time to freak out?  Um... yeah.

I truly dislike Tennessee's state standards for chemistry.  I have not compared them to other state's standards, but I find them entirely too broad, yet detailed at the same time.  There is no possible way you can teach your average junior EVERYTHING in our chemistry standards to the level of mastery they expect in a single course.  They expect them to understand atomic theory in depth from Democritus thru the quantum model.  They expect them to draw Bohr models and understand, write, and identify electron configuration.  They expect them to know properties of matter, including properties of solutions, colligative properties, molarity, molality-- the later two they need to know how to calculate.  They are supposed to know thermochem and calorimetry-- including solving specific heat problems.  Heat of solvation, heat of reaction, heat of formation, and heat of phase change are all in the standards.  They expect them to understand the kinetic molecular theory of matter and solve gas law problems: combined gas law and ideal gas law.  They need to know about the arrangement of the periodic table.  They need to write the proper and common names of ionic and covalent compounds and understand the bonding.  They need to know polyatomic ions.  They need to be able to balance chemical and nuclear equations.  They need to be able to write net ionics and predict reaction products from the 5 main types of chemical reactions.  They need to know acid/base reactions, they need to use an activity series, they need to do stoichiometry problems.  They need to differentiate between alpha, beta, and gamma radiation and utilize half-lives.  They need to know about heat transfer in both chemical and nuclear reactions.  They need to differentiate between nuclear fission and fusion.  They're supposed to be able to argue the pros and cons of nuclear energy.  And I haven't even gotten to the math standards:  percent composition, percent yield, percent error, graphing, unit conversions, sig figs, accuracy/precision in measurements.  Then there's also inquiry standards and embedded engineering standards.  IT'S TOO MUCH!!!!!!

I have never been able to get through all of the chemistry standards in my entire career.  Most of my co-workers have the same problem.  The few that brag about easily completing all of the standards are the "textbook" teachers-- read a chapter, answer the questions, take a test.  They don't spend time on labs (which "perform and understand laboratory procedures" is indeed one of the inquiry standards).  At the end of the course, the students come away with nothing.

I'm not proud of how this semester has gone, but I still believe I can make the chemistry modeling curriculum work for me and my students with some tweaking.

Unit 7 Chemical Reactions - Rearranging Atoms

If you had spoken to me yesterday, you would have heard how proud I was of my students.  But today is not yesterday, and once again I'm slamming my head against the desk.

We spent Monday through Wednesday on nomenclature and chemical formulas of ionic and covalent (molecular) compounds.  It was a lot of direct teaching, and we completed Unit 6 Worksheets 3 and 4 as assessment.  They worked extremely hard on something I would consider pretty boring and they were showing a strong mastery.

Today, we took a quiz on nomenclature.  I didn't use the AMTA quiz, but rather copied question #10 straight off the AMTA Unit 6 test.  (For the sake of time, I'm combing these last units into one unit test so we have more days for instruction before the EOC) They had to identify formulas or names as ionic or covalent, then write the name and/or formula.

The grades... so horrible... oh my gosh.  I would have NEVER anticipated the grades being so terrible based off what the students produced on worksheets 3 & 4 and our other in-class practice.  Most students couldn't even correctly identify the compounds as ionic or covalent, which we've been doing in class for DAYS.  So it looks like I'll be re-teaching the topic tomorrow.

The other plan for today was to begin Unit 7 by completing the Rearranging Atoms activity.  We do not have time for the nail lab, so I figured this would be a good way to introduce balancing equations.  The plan was to do the Describing Chemical Reactions lab tomorrow, since today's activity seemed very straight forward.  I foolishly assumed we'd be able to complete it in about 45 minutes and be balancing equations successfully for homework.  Ha!

First, the activity begins with 5 background questions that should be 100% review (ignore the copier line):

For some reason, these were the 5 most difficult questions in the world and my students SHUT DOWN instead of trying at all.  This caused me to just get ticked off, since none of these should have been a challenge.  There is zero excuse for them not to be able to answer any of these questions.  I basically let them have it and told them if they can't answer these 5 questions, not only have they shown me they aren't ready to go do chemical reactions in the lab tomorrow, but they don't even deserve to pass the course.  I was pissed.  There was a small standoff in just about every single one of my classes over these questions, and I refused to cave until they answered them and explained their answers.  After 14 weeks of chemistry, I should not have to spoon-feed my juniors answers to review questions that not only have been covered in my course, but were covered extensively in middle school and 9th grade physical science.  Maybe other teachers are content giving them the answers all the time, but the students should realize by now that they can't get away with that in my classroom.  Yet they still throw a temper tantrum any time I expect them to think (if you could even call those questions "thinking"- isn't describing like level 2 on Bloom's taxonomy?) and it's getting really old.

Anyways... after the background questions, students are to use atomic model kits to model the reactants given for a series of chemical reactions.  Students are to then build the products from the reactants.  If they don't have enough atoms or have left over atoms, they need to start over using additional reactants.

Once students find the correct ratio of reactants to products, they are to draw a particle diagram of the reactants and products and put the numbers of molecules of each in the blanks.

My first class just did not understand at all and we ran out of time.  My second class also did not understand at all... so I modeled how to do #1 and 2 at the front of the room.  They were still lost and we ran out of time.  By my third class of the day, some groups were sort of getting it, but many were still lost and surprise surprise, we ran out of time.

What was truly amazing to me was that I kept asking random students if they could guess what we were trying to do to the chemical equation.  Every single one of them said "no."  I figured someone would realize we were just balancing the equations, but nope.

Unit 6 Reflections: Conductivity Activity and Worksheet #1

My endearing students have started leaving chemistry jokes on my board before or after class:

At least not everyone has a bad attitude!

I'm still plugging away at as much of the modeling curriculum as possible, despite being ridiculously far behind.  As I mentioned in my last post, I made a decision to replace the "Sticky Tape Lab" with a simple static electricity activity.  It seemed effective and we were able to replace a lot of the time we would have spent on the sticky tape discussion with some coverage of the periodic table and the ionization trends on the periodic table.

I got it in my head that I really wanted to use the property of conductivity to help students identify the difference between ionic and covalent.  Every year I seem to want to demonstrate conductivity, but my school has never had any conductivity probes.

Some wonderful teachers at my modeling workshop introduced me to the idea of making conductivity probes out of 9v batteries and Christmas lights.  I found a couple ideas about the best way to do this online, then headed to Walmart to see what I could find.

I came up with these:

Homemade conductivity probe

Basically, I bought a strand of $5 Christmas lights and cut a lightbulb out of the strand for each probe.  The length of wire between each bulb is extremely short, so I also used the excess loopback wire and an alligator clip to give more length.  The alligator clips were in the automotive department surprisingly, and cost about $2 for a pack of 6.  The batteries were less than a dollar a piece, and the entire thing is taped to a popsicle stick for ease of use.  I spent around $20 and it took me about an hour to construct a set of 7 for my classes.  If I had more time, I would have had the students make them on their own.  I know a lot of my boys would have really dug that.

Of course, the day we hit this in the curriculum, all of the science labs were being used by other teachers.  So, I grabbed an assortment of substances that would be easy and safe to use in the classroom:

The procedure was to classify the elements as metals, nonmetals, and metalloids and test their conductivity.  Then students classified the compounds as M-NM or NMs only and tested their conductivity dry and then dissolved in H2O.

As usual, my first class of the day nailed it.  I was particularly proud of this group:

We just whiteboarded the data for comparison and verbal conclusions

Their terminology could have been better, but you have to understand that this was a group of 4 extremely low-performing and unmotivated boys who saw the pattern immediately.

After we discussed how M-NM compounds are conductive dissolved in solution, but NM-NM compounds are not, I gave my students Worksheet 1.  We did not have time to even touch the electrolysis of copper chloride lab.

Worksheet 1 is hard.  Ideally, the goal is for students to deduce both the ratios of ionic compounds and the oxidation numbers of each group all via the concept that solid M-NM do not conduct electricity.  That's a lot to discover on their own.  Now, before the conductivity lab, I taught my students about oxidation numbers when I taught them cations and anions.  But they still had to determine why compounds form in certain ratios.  It's a really good worksheet.  And oh my gosh, did my students complain and whine.  But... they figured out how to write binary ionic compounds all on their own and could articulate why.   I'm sure hoping the retain this understanding over the weekend!

I did not plan on going into great depth on the structures of ionic vs. molecular solids, but I did download the Mercury Software.  I like the idea of showing them the difference, but I could not get the software to work correctly for me and just didn't have time to play with it.  Instead, I'm falling back on an old powerpoint and some direct teaching for the differences between the chemical bonds and nomenclature.  I do intend to complete worksheets 3 and 4 next week and Quiz 1, but then I'm moving on.

Kicking off Unit 6

This has been the semester from h*ll.  Have I already said that?  Yeah, I think I have.

Last week was spring break, which was absolutely lovely.  Prior to spring break, we flew through Unit 5 in about 4 days.  The students learned about the mole, they learned how to do conversions with Avogadro's number, and they learned how to do molar mass conversions.  No real labs, and I barely used the modeling curriculum-- just previous year's PowerPoints and grill & drill practice worksheets.  We ran out of time before spring break to do percent composition and empirical formulas.  I will pick them up at some other point in time... IF there is time.  The EOC is in 4 weeks and we have so much to do.

Today we began Unit 6 with a "charge" lab.  I chose not to do the Sticky Tape Lab.  In my modeling workshop, I remembered that lab being extremely time consuming.  We DO NOT have time. Instead, I adapted a lab I have used in the past called "Electrons on the Move," which can be completed in less than 30 minutes.  Obviously I did not call it that this time around-- we referred to it as "The Charges of Matter" lab.

Basically, it's a static electricity lab composed of six stations.  Students rub balloons and plastic objects on fabric and see the attractions and repulsions.

Before the lab, we discussed Democritus and Dalton's atomic theories, then I told them there was another scientist named JJ Thomson who added to the atomic theory based off his work with electrical charges.  We discussed the idea of charges.  Where have we seen positive/negative charges or ends of something in the lab so far (batteries, magnets)?  We discussed how like charges repel, opposite charges attract.  They were told the purpose of the lab was to determine if the objects in the lab had charges.  They were to draw a before and after sketch of each station, then assign charges to the objects.

Each lab group was assigned a single station to whiteboarded a verbal explanation and a diagram, both of the charges and of the particles.

Some examples (missing station 6):

Um... sort of not really

A little better

Not too bad

At least they were thinking about it

As a class, we came to the conclusion that:
1. Matter can have positive, negative, or neutral charges.
2. The charge of matter can change.
3. In the lab, the charge changed without changing the particles.

We didn't go into details on "positive" and "negative" yet.  Most have at ton of misconceptions in that department, but hopefully we'll clear them up tomorrow when we introduce the idea of electrons.

I sent them home with the online notes activity about JJ Thomson's experiments included in the curriculum.  It links students to A Look Inside The Atom to learn about JJ Thomson's cathode ray experiments.  I hope to heck that at least some of them attempt it so we can move on quickly.

Unit 4 Reflections: Worksheet 1 and Electrolysis of Water

Going by the modeling "book" is not working for me lately.

Friday: I expected pure substances vs. mixtures to be a review for my students, especially after the feedback I was receiving in our post-lab discussion.  The topics are covered heavily in physical science. The students usually blow right through it in years past.  I thought it would be a great chance to squeeze in some much needed textbook reading/writing practice, with it being a familiar topic that is not all that difficult to grasp from reading.

Um... no.  That's not how it went with these students.

Friday, in class, they were assigned to read the (very short) unit out of the textbook on classification of matter.  They were then to write me a paragraph classifying the stuff we saw in the lab (salt, sand, iron, salt/sand/iron together, water, sulfur, iron, iron sulfide) as a pure substance or a mixture using vocabulary they read in the text.  I figured after they read about the topic, we'd jump right into Worksheet 1 on Monday.

What they actually did instead of reading-- sit with the book in front of them without flipping a page, then turned in a list of garbage that showed they didn't even as much look at the headings on the pages.  Not cool.  I know it was Friday, but COME ON.

So, I got to spend all of Monday reteaching what they didn't read in the book.  I did it in a PowerPoint that I've used in the past, then finally gave them Woksheet 1.

I've never understood why this is so hard for students:

I used to assign a similar worksheet in years past and my students went into panic mode when they saw it.  After my Modeling Workshop, it occurred to me that I was assuming that students had a conceptual picture of particles when it was something I truly never taught.  This year, since we have been explicitly working in conceptual "particle" mode all year, I didn't anticipate it being nearly as panic inducing.  Wrong again.  *head desk*

So we wasted more time today slooooowly correcting the very wrong answers on Worksheet 1 until it finally seemed like my students had some idea of the difference between elements, compounds, and mixtures.

Onward ho-- next we were supposed to start building towards the Law of Definite Proportions with a demonstration using a Hoffman Apparatus.  My Modeling Workshop was generous enough to provide us all with our very own Hoffman Apparatus!  Unfortunately, they didn't give us a power source.  Never fear, they told us, you can just use a 6V or 9V battery.  Ha.  Hahaha.  Ha. Of course, I procrastinated until the last minute to try this idea and found that while a battery will cause some decomposition, I could not get the reaction to go nearly fast enough to be visually impressive.  Maybe it was just me.

I needed a backup plan.  My first thought was to do the 9V battery/pencil lead electrolysis of water-- but a single set up is way too small for an effective demo.  Plus, I really wanted them to see that it was twice as much hydrogen than oxygen, and actually prove it was hydrogen/oxygen and not just bubbles.

Thanks to Google and YouTube, at the 11th hour I was able to rig up some of these setups using materials I had on hand:

Small plastic container with two push pins through the bottom, 2 test tubes, a 9V battery, and a solution of water with a small amount of sodium biocarbonate

The containers were a little cumbersome to manipulate, but the setup worked well overall.  Between weak batteries and time constraints, we didn't see a perfect 2:1 ratio, but the students clearly saw more gas being formed on the cathode side than on the anode side.  I was able to come around with a flaming splint and demonstrate the hydrogen "pop" to each group.  There wasn't quite enough oxygen to re-ignite a hot splint, but it was enough to at least make the flame visually grow.  We discussed how water vapor would not cause a flame to grow or pop-- too much water vapor may even extinguish a flame.  We also discussed that the container did not feel hot enough to be boiling, so it couldn't be "boiling" water.

I told them that scientists have found that a compound of a substance always has the same ratio of elements.  Water is always 2H:1O.  We then hypothesized the ratios of elements in other familiar compounds, like sodium chloride and glucose.

We were going to watch "Gases and How They Combine," as suggested by the lesson plan.  I watched the video myself on YouTube and it is BORING and dated.  While the demonstrations and explanations are great, I don't see my students paying enough attention to get anything out of it.  I think we'll jump right into Worksheet 2 tomorrow... then on to Dalton's Playhouse.

Despite being dreadfully far behind and feeling like 50% of my students are shut down... I do hope that by the time we get to balancing equations, it should be a non-issue.  That's basically all they are doing in Worksheet 2.

Unit 4 Reflections: Separating A Mixture

I've had to shake things up a lot.  Last week, we had two more snow days and two days where I lost my students to standardized testing.  I basically said to heck with the rest of Unit 3.  We didn't do any of the specific heat calculations.  We quizzed on the types of energy, energy bar charts, heating/cooling curves, and phase diagrams (my addition) and called it a loss.

I'm also shaking up Unit 4 a bit.  For starters, it begins with demos and discussion.  Unless I'm blowing something up, my unmotivated, under engaged juniors don't give a darn about demos.  And I've been struggling all year to get my students to buy in to group discussion-- it does not happen easily.  I truly needed to get them in the lab.  I fell back on the old "Separation of a Mixture" lab, an activity that I usually do at the beginning of the year to introduce them to the concept of experimental design and properties and mixtures.

We started Unit 4 by defining properties, then differentiating between physical and chemical properties.  I then gave them a sample of salt, sand, and iron filings and asked them to develop a plan, using their properties, to separate the three substances.  I offered them a list of available materials to help them out.  Considering I rushed them a bit on their experimental design process, they didn't do too terribly.

Overall, I was really impressed with my student's white boards with the exception of their particle diagrams.  I was very specific for the verbal this time:  I asked them to answer the question, "Why were we able to separate the three substances?"  I was very specific for their math as well, and told them to show me how to calculate the percent composition of the mixture.  I left the graphing and particle diagrams completely open ended, asking them to do what they felt was appropriate.

Most boards looked like this:

Strong answers to the questions, good math, appropriate method of graphing data, dreadful particle diagrams (WTF?), and an overall inability to spell the word "separating."

We addressed the particle diagram issue today.  I hope they got the point-- everyone was utterly braindead today.

Unfortunately, many of my lazy students have caught on that I don't actually grade whiteboards.  So, several groups produced garbage like this:

At least they figured out how to calculate percent composition...

Um... yeah.

I also performed the demonstration of heating iron and sulfur.  This is a demo I had never done before.  I could not get it to react with a hot stirring rod or hot splint.  I ended up using a ring stand, a heavy watch glass, and a bunsen burner.  The odor is horrific and the ignition was not all that impressive to the students.  I think the bunsen burner flame confused them- they just thought it was flammable even though I made a point of showing how far away the flame was from the iron ring.  But, they were able to see that we got a substance with different properties from either of the original two substances.  We left off with a textbook reading about pure substances vs. mixtures.

We'll do worksheet 1 on Monday.  I haven't shown them fractional distillation equipment (we don't even own any), so I suppose I should do that first!  Youtube here we come...

On a side note, my students had to take a district wide benchmark test today.  It was created with traditional pacing in mind, so many of the topics we have not covered.  When I flipped through the test, I figured there were about 11 out of 30 questions that my students should be capable of answering.  I was at least encouraged to see that my students mostly got those 11 questions correct.

Unit 3 Reflections: Icy Hot Lab Results

This is becoming the semester from h*ll.  Seriously.  Between implementing the chemistry modeling curriculum for the first time, the exceptionally unmotivated group of students, and the ridiculous number of interruptions, I'm ready to throw in the towel.

The good news:  my students' data came out better than expected.  Even in my first class, students were able to note a difference in the shape and slope of the heating and cooling curves at different points.

Some of their curves:

The bad news:  everything else.

I think maybe a handful of students at best understood what I think is a pretty easy concept.  A heating/cooling curve will have parts of the line that show little rate of change (flat) because the energy is being used to "break" the forces of attraction between the particles and change the matter into a different phase.

I don't know exactly what it is that I'm doing so terribly wrong, but I cannot get these students to care for the life of me.  I can't even get enough intrinsic respect out of them to try for me.  Two of my students today told me they hate everything about science.  I can't even fathom having the lack of respect to say that to my teacher when I was that age.  And all of this because they were asked to graph some data... which took nearly all of the 90 minutes to do, and do poorly at that.  Not that I told them that last part, but sheesh, look at those graphs-- do they look like work products that should have taken an hour to produce?!?  Notice there isn't a verbal conclusion or a particle diagram on any of them.  Let me just say there was supposed to be each of those as well.

I'm scared for the lab reports.  They are not going to be good.

Today really got me thinking about another teacher from my modeling workshop.  She mentioned that a constant problem she has with "inquiry" type labs, is that the students mess up, take away the wrong idea, and don't care enough to change their thinking.  That's very much what I saw with my students today.  I asked me students how they thought their graphs were going to look-- most said heating ice would be a straight increase, cooling the lauric acid would be a straight decrease.  After they (finally) plotted the data, I asked if that's what they saw.  Yup, they told me.  I asked about the flat areas and the zigzags-- it must have been the hot plate.  Or *maybe* it was human error.  They don't care, the line went up at a point, so they were all correct in their minds.

Can I just get a do-over on this semester?  I think if I had to do it all over again, I'd start WAY easier on this group and build up a better relationship with them.  I set the bar high and was hard on these students from the start, and they have now shut down on me.