Tue, 10 May 2011

Shiny Stuff!
I got my battery frame panels at the end of the weekend, and they look really cool:

To get these I had to:

• Make up cardboard mock-ups of the panels I wanted
• Design them in QCAD
• Add a bunch of extra tabs for mounting, on the principle that it's much easier to remove metal than to add it
• Send the designs off to Serafin
• Serafin don't have the 3mm aluminium plate that I want, so organise for Onesteel to send a sheet of it to Serafin - the smallest sheet they have is 2.4m by 1.2m
• For otiose reasons, organise a friend to collect and pay for the cut plates - he also videod the process, which I will put up as soon as I get my hands on the files

And how much is that? Well, according to NCOP 14, the frame has to hold the batteries against 20 Gs of force from the front, 15 Gs from the side, and 10 Gs from rear, top and bottom. With 83 Kgs, this means I have to support about 1245 Kgs from the side. In other words, I have to imagine the bike hanging on its side and 1.2 tonnes hanging directly from the central battery frame panel.

And, you know, I'm pretty confident of that. Most of that weight is going to be directly transferred to the frame, which is already designed to take that carrying the combustion engine anyway. The panels feel strong enough to hold that load and transfer it to the bike frame easily. The edges, from the water jet, feel a bit rough but the corners are sharp and there's no tearing or wavering. Now to actually get enough time to start putting bits of it in the bike! (I need to find a tame person with a decent metal brake to do some of these bends, though...)

posted at: 15:54 | path: /personal/ebike | permanent link to this entry

Performance Pay for teachers considered harmful
Mikal Still blathers about performance pay for teachers - he thinks that "the only people who object to performance pay are those who secretly know they under perform?".

Well, I for one object, and they're worth a blog post.

The problem is: how do you judge the teacher's actual performance? How do you separate this from the abilities of their class? How do you know, empirically and repeatably, that they're better than another teacher?

The answer is: you can't. A teacher's ability to teach is an intangible thing, like an artist's ability to create. It covers not only the obvious skills of passing on information and concepts, but also their ability to engage the class, work with good and bad students, and to keep the whole group interested and active. The best teachers I've had have not been those in which my entire class did brilliantly, or where our class's results were demonstrably better than the others. They've inspired me, sure - but maybe other people in the class still found it a chore, or just didn't care that much about the subject.

And we've already seen teachers cheating on marking students' work to make sure their class gets a better grade. Link that to pay and there will be a much bigger reward for that kind of bad behaviour. Then you have to have all sorts of extra supervision and suspicion, which costs money to implement and hurts morale. And exactly how do you say "this person's artwork isn't as good as you marked it"?

And how do you reward the teacher aide who got given the entire year's worth of difficult students to babysit while the teachers went off and rewarded their talented students? By assessing how their problem children went? This happens even now.

Morally, judging one person by the performance of other people is wrong, especially when those other people are affected by a lot of other factors besides the teacher's 'ability to teach'. Would one suggest performance pay for police based on the amount of crime in their suburb?

And practically, no-one who suggests 'performance' pay for teachers also suggests increasing their average pay. So it's only rewarding those that artificially do well by cutting pay from those who already can't afford it. This doesn't trim the fat, it only makes the back-stabbing and cheating pay off more.

The larger question is really "what will it take to get teachers to be better respected in our society?". The answer, in my opinion, is three fold:

1. Take back the control of how things are taught from people in the education department, who may never have taught in a classroom or done an education degree, and give it to a body of teachers who have real-world experience.
2. Pay the teaching profession in proportion to the amount of work they actually do now. Teachers are treated as if their job is simply from nine to three, but in real life every teacher I know has spent countless hours before and after school and on weekends preparing lessons, doing research, marking, helping some students, training, watching over the children outside of lessons (e.g. 'playground duty') and more. Teaching is paid as a thirty hour a week job where it's more like a sixty hour a week job.
3. Don't make education the forgotten cousin in the budget. We waste billions of dollars on defence projects that never see the light of day, millions are spent commissioning great swathes of reports which are never acted on, yet the increase in actual school funding is minimal.

"It will be a great day when schools get all the money they need and the army has to run a cake stall to buy a tank."

posted at: 14:36 | path: /personal/rants | permanent link to this entry

All posts licensed under the CC-BY-NC license. Author Paul Wayper.

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