Discussions from the magazine, website and social media

Talk Chemistry

Timing and planning

All sorts of topics have been discussed on Talk Chemistry this month. The most popular thread was started by a chemistry teacher from Beijing, China, whose question on timing and planning chemistry lessons provoked a lively exchange of ideas. Yitao Duan asked:

I’m currently teaching KS3 science, iGCSE chemistry and International Baccalaureate Diploma Programme chemistry. However I’m finding it very difficult to time my lessons. Each period is 55 minutes long. However it’s often the case that I teach from my Microsoft PowerPoint slides for the entire duration of the lesson. Is this very bad pedagogy? When I try to make it interactive by asking them questions (including prior knowledge from the previous lesson), my pupils feel that I’m going too slowly. But if I go faster, I feel like I’m teaching like a robot ie by merely reading off the slides. I also find it very hard to have a plenary as I often fail to cover material which I originally intended to cover. How could I resolve this conundrum?

On a related note, do you think it’s absolutely integral for me to lay out the learning objectives and outcomes? Finally, it’s very hard to differentiate as this would involve giving different worksheets to different pupils and that would be like ‘labelling’ them.

Advice and ideas for Yitao came from many contributors, and a fascinating discussion followed. Here’s a highlight from what Keith Ross had to say:

It is one thing to tell students something but quite another for them to be able to tell it back to you or to a friend, yet that is what you want – the students need to understand ideas not just regurgitate them. That is why I use the ‘tell each other’ technique in several places in the lesson – instead of them answering your question by putting their hands up you ask them to ‘tell their partner’ involving them all, and they do not need to be embarrassed to speak in open class. This can even be done in their native language, especially if you then say ‘OK now say that again in English’.

YouTube in lessons

Do you have access to YouTube in your classroom? Does the school or local authority block it? Please let us know


Empowering students

In last issue Simon Lancaster and David Read examined flipped teaching, the current technique that empowers students to take control of their own learning. This has been the most popular article on our website from the September issue, and it has generated some comment on LinkedIn too.

Julie Pfordresher spoke from experience:

I used flipped teaching at the high school level. I would refer to my homework assignments as ‘preview’ homework instead of the typical ‘review’ homework. I would have students view a Microsoft PowerPoint presentation and answer a few questions. The discussions and questions the next day were always more meaningful than when I assigned review homework. It was also a great way to lessen the excuses of ‘I was absent ...’ because students wouldn’t need access to me or the class they missed to do the assignment. This is less of an issue on the college level but it worked great for high school!

Alfredo Tifi shared his opinion:

I appreciate that in flipped education you don’t waste time explaining from one to many in a monologue. But the illusion that understanding could be made by listening to someone’s speech, without doing, constructing and collaborating through trial, error and engagement in solving problems, is simply transferred to the student at home, not eliminated.

Philip Morgan is very much in favour:

This is a very insightful article. I think, with the growth and development in technology, the flipped teaching model too has evolved. It is being preferred as the mode of education by many, due to its numerous benefits.

Finally, read about how a university in the US successfully flipped the teaching of their introductory chemistry courses and how their students respond.

Virtually as good?

In September we reported on how a virtual laboratory exercise in electrolysis can help to prevent students acquiring misconceptions in their scientific understanding as a result of cost-cutting measures in practical science.

George Dad had this to say:

Not being judgmental here, as schools are going to do what they want to do regardless of data to the contrary – you just need to find a study that supports your point of view.

The article doesn’t present what was post-tested, so I can’t assess the efficacy of either approach. So, just some observations:

That students doing the hands-on lab put the electrodes themselves in solutions indicates that a person is required to catch this error and discuss why this will elicit results which do not characterise the potential of the metals – this conceptual flaw is not discovered with a simulation that precludes setting up the equipment incorrectly.

Selecting alternatives to the salt bridge, such as low-budget string soaked in KNO3 solution, is a good thing to learn. What you want may not always be available and you may have to improvise.

Corrosion on the electrode metal samples sometimes requires ‘jiggling’ the alligator clip probes to get better conductivity, too – a simulation probably doesn’t include that. Is that nitpicking, or does it speak to the nuances of reality that we experience in the real lab world? These details speak to our problem-solving skills, though (forgive the cliche) ‘achieving learning outcomes’ may still be demonstrated.

It’s important to know everything that could possibly happen – every conceivable permutation and combination in advance, before you have to put a zinc plate on the hull of a ship, bolt a steel car fender on with an aluminum alloy bolt, salt the highway containing rebar over a bridge or not rotate the camera platform on your Voyager space probe for several months.

I’m virtually certain cost-cutting will have no significant impact on reality.