this post was submitted on 04 Dec 2023
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This guy is apparently a widely cited education scholar not an extremist Marxist or whatever: "You Can’t Get There from Here" Johnstone 2010 [PDF]: https://sci-hub.se/10.1021/ed800026d

"capitalist competition makes us stronger and more innovative"

sorry radlibs but there's a reason why 35% of students in your shitty designed STEM classes drop out, they aren't stupid for getting bad grades. You're the stupid one for being so ignorant that you've managed to fail to educate people for over 60 years. I take back everything I said about "western kids want to be Twitch streaming gamers lol they're losers", these families literally have not had access to a decent science education for three generations!

Are we still persisting in making our students sick of chemistry because “that is how chemistry is done here”? Who set the scene? How did it all come about?

The answer lies not with some malevolent group of people, but with a response made in the 1960s in the United States and throughout the Western world to combat the perceived threat of Russian scientific supremacy. ChemStudy and Chemical Bond Approach sprang up in the United States, Scottish Alternative Chemistry and Nuffield Chemistry appeared in the UK, and similar schemes were launched

the PMC class of finance imperialism educators are a malevolent group of people, Jeffrey Epstein was a NYC math teacher amber

his suggestions for improved chem curriculum

Begin with the idea of the filter that is driven by what the learners already know and by what interests them. There is no point in beginning a course in chemistry with a treatment of atomic electronic configuration or bonding because the anchorages in long-term memory are not there. Without attachments in long-term memory, a student can only learn by rote methods. An approach to chemistry through acids, bases, and salts is unlikely to stir students with enthusiasm. Apart from common table salt, how many salts are in place in long-term memory to provide relevance and reality for the learner? On the face of it, inorganic compounds are “simple”, but are they? So many wrong concepts are introduced by teachers or constructed by the learners in this area of chemistry. A glance at a book of chemical data will show the absurdity of suggesting that sodium (or any other metal) is “anxious” to lose electrons and chlorine is “desperate” to accept them. It is too soon to introduce lattice energy or hydration energy to provide a rational basis for compound formation. The octet rule, with all its pitfalls for later study, tends to raise its ugly head here as a sort of rationalization.

The model suggests that we should begin where students are, with their interests and experience, and lead them into discovering new ideas among the familiar. An obvious starting point is in organic chemistry, with gasoline, camping gas, food, clothing, plastics, and drinks and so much more that is familiar. I know that it has been the tradition to keep organic for later, but are we taking a “monkey” point of view? Let us consider some of the advantages in starting here.

The long-term memory already contains anchorages for what we want to teach and the filter is primed and ready to go. The working memory is not in danger of overload. We can go a long way into organic chemistry with only a few elements: carbon, hydrogen, oxygen, nitrogen, and possibly sulfur and phosphorus. Most of these are familiar (at least their names are) to the learner. By considering the spatial arrangement of the four electrons around a carbon, students, using their fingers, can see that a tetrahedral arrangement is likely. Never mind sp3 hybridization. It is a cobbling together of atomic orbitals (isolated atoms in the gas state) to produce a tetrahedron. This is using unreality to arrive at reality. Pasteur knew about the tetrahedral arrangement long before atomic orbitals were conceived.

Using the simple tetrahedral idea, we can do a lot of sound organic chemistry linked to what the students already know, avoiding overload of working memory. Only when we reach organic acids do we have to reconsider bonding, but this can now be linked to the simpler ideas of covalent bonding already established. Another advantage of beginning with organic is that there is no pressure to use balanced equations. Practicing organic chemists do not bother, so why should we?

The model has led us to select a starting point that fits what is already in a student's long-term memory. The working memory is not overloaded because only a few elements are involved in making familiar compounds. The representation triangle can be used along its sides to build ideas of the relationship between the macro and familiar, with the molecular. The use of the representational is reduced, and no calculations are necessary. All of this provides a logical basis for an applications-led approach instead of a conceptual approach followed by a passing mention of uses and applications.

The troublesome mole can be rethought in the light of the model. It has been my sad experience to have graduate students who confessed their inability to do mole calculations. The very word “mole” left them uncomfortable. How could highly intelligent young people have such an aversion? They met the mole too soon, wrapped up in incomprehensible (and even totally irrelevant) calculations that flooded the working memory into a state of paralysis. In an earlier publication (4) I set out an analysis of a trivial (from my point of view) mole calculation. I saw it as a four-step procedure, which did not tax my working memory, because I already had tricks for grouping the processes, but students saw it as a ten-step task, which blew their working memory.

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[–] [email protected] 8 points 11 months ago (2 children)

I feel like it's hard to cut to the chase for anything chemistry without atomic bonds and charges. Even if you're talking about gasoline, or camp fires, your elementary lesson is going to include a balanced equation (a balanced equation of what? Molecules). Because I think it might be cool to be like "check out this dope ass machine, it does chromatography." You're still going to have to talk about polarity or mass being used to separate molecules (and what's a molecule anyway?). If you want to be like "check out this dope ass picture of a snowflake" to talk about an electron microscope, you're still talking about charges.

I'm having trouble imagining an applications-led approach without some basis in nerd shit.

[–] [email protected] 2 points 11 months ago* (last edited 11 months ago) (1 children)

I slightly disagree.

When learning anything there's always an extra layer of depth one can go into when explaining things. And the reverse is always true, there is always a layer of depth you can stop at before going deeper. Teaching children the basics of chemistry to a point that it's functional for understanding the world around them in a way they need to without all the "nerd shit" is possible. I'm from the UK (didn't do Nuffield chemistry) and at GCSE level we were taught orbitals are the simple rings with 8 electrons in each orbital ring (and 2 in the innermost one). We were taught this as fact even though the teachers knew this was not accurate information, and the concept of s, p and f orbitals were never even mentioned in our lessons. It wasn't until I did my A levels that we were taught about s, p and f orbitals and the simplified GCSE explanation helped introduce this concept to me (although I'm aware I only speak for myself). The simple 8 electrons per one orbital ring model is outdated and scientifically inaccurate (I assume, I'm not a chemist lol) but still helpful. The same way there are probably many simplified explanations for what molecules are, or what the concept of polarity is without having to make things unnecessarily complicated to kids learning about chemistry for the first time.

I guess this is why we as a society need to make the field of teaching more evidence-based to find out which solution using these concepts is the best and most effective way to make concepts stick. But in my opinion, the way I've internalised information the best way even when things get harder down the line is just being taught a very simplified, maybe even outdated model to expand upon later.

[–] [email protected] 1 points 11 months ago

If you pressed me on it or had a professional tackle the problem, I suppose you could find a super simplified model to teach elementary concepts. If you made sense of molecules as balls and sticks, styrofoam and toothpicks, then you could explain functionally what they're capable of doing. Perhaps I was getting ahead of myself: the relatively steep learning curve is a problem to be tackled, that shouldn't be an endorsement of the way things have always been