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Archive for May, 2015

Dumbed down markschemes?

May 22, 2015 2 comments

Today I was working through the June 2014 Edexcel M1 paper for my year 13s, noting down thought processes etc and I arrived at this question:

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It’s quite a nice, general bouncing ball question that takes into account many of the rules of mechanics. When I finished the question I checked it against the markscheme so I could jot down where each mark came from and on part E I received a bit if a shock.

The weight of the ball is given as is the distance it’s dropped from and the distance it bounces to. In earlier parts of the question you have been asked to calculate the final speed of the bit before the first bounce and the initial speed after. Part E asks for the time between the ball being dropped and the second bounce. I split it into to, used s = ut + (1/2)at^2 (u=0, s=2,a=9.8) to find the time it took to drop, then the same equation for the time between bounces (this time s=0, u= the value already calculated, a=(-9.8)). A simple question, a simple solution and a nice answer. The markscheme, however, says this:

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I don’t understand why they have felt the need to work out the time between the first bounce and the top then double it. It’s a valid mrthod, granted, but surely looking at the whole motion is sensible as acceleration is constant?

Worryingly, in the notes there’s no other solutions offered and I was left wondering if examiner’s might miss that thus method is not only correct,, but actually more sensible.

Which way would you have done it? Do you think I’m correct thinking mines the mire logical sensible way?

Revenge of the real life questions

May 21, 2015 7 comments

Last year I wrote this piece discussing some of the worst pseudo-contexts that I’d come across in maths exams. You know the ones, the ridiculous made up contexts that are supposed to give a real life twist to a question but Ard actually anything but. Well this year’s C2 Edexcel A Level paper has two of the worst I’ve ever seen!

Exhibit A

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Aaaaaaaarrrrrrggggghhhhhh!!!!!!

“Figure 1 shows a sketch of a design for a scraper blade. The blade OABCDA consists of an isosceles triangle COD joined along its equal sides to sectors OAB and OCD of a circle with centre 0 and radius 8cm. Angles AOD and BOC are equal. AOB is a straight line and is parallel to the line DC. DC has length 7cm.”

There are a few issues I have with this question. Firstly we have a whole paragraph that is entirely unnecessary! The only purpose this paragraph would serve was to test the ability to sketch or visualise but this us completely negated  by the diagram. One of my year 12s asked, “what’s the point in that writing on the sectors question? It just described the picture.” I had to agree.

That wasn’t the worst bit though, the worst bit is there at the beginning .

“Figure 1 shows a sketch of a design for a scraper blade”

I can imagine the examiner’s meeting now: “I’ve got a great sectors question, it uses area, arc length, cosine rule, sine rule for area…. it’s a classic.” “Great, but we said that was going to be a real life question this year.” “Oh b@#@##ks, what can I do?” “Just make it about a scraper blade!”

What even is a scraper blade, and why do we need this question be about one?! This was actually a great question, or would have been if it had only one of the picture or the paragraph and no stupid mention of a scraper blade.

Exhibit B

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“A solid glass cylinder, which is used in an expensive laser amplifier, has a volume of 75pi cm^3.
The cost of polishing the surface area of this glass cylinder is £2 per cm^2 for the curved surface and £3 per cm^2 for the circular top and base areas. Given that the radius is r cm…”

Show that the cost is, then find the minimum.

This question is pseudo-context at its worst. A part for an expensive laser amplifier will be the required size for said amplifier. It will need to fit abd as such it’s length and radius will be far more important that it’s volume, do there’s no way at all that they would design the laser around the minimum cost of polishing a cylinder with a certain volume! Why would you create such a convoluted, nonsensical, bogus context?! If you want to ask questions in context fine, but please make it a believable one!

Freedom?

May 18, 2015 Leave a comment

This post was originally posted here on Labour Teachers.

A favourite piece of policy from our Education Secretary seems to be the introduction of new “Free Schools”. It was the baby of her predecessor and was an extension of the academies project.

I have a few issues with free schools. Firstly, they are often built in areas that have no real need, leaving a surplus of school places in some regions and a deficit in other. This can lead to some parents having to arrange travel over quite long distances to ensure their offspring can attend school. The fact that parents in less well off areas don’t have the means to ensure free schools open in their vicinity means that they are often the areas that end up with a deficit of places and larger travel bills.

The other main issue I have with them is the added freedoms they have, which I believe are the same freedoms given to academies. I worry that these freedoms can cause a larger inequality within the state education sector. I’m a fan of the idea of a national curriculum, a minimum standard that all students should be a party to, but academies and free schools don’t have to stick to it. This could put some young people in a much better place than others depending on their school.

I was against the principle of academies when the last Labour government introduced them. The idea that “state” education could be run by chains that were based on a business model clashed with my ideological viewpoint. But I could at least see the idea came from the right place, from the idea of putting more money into failing schools. The roll out under Gove to put more money into already outstanding schools seemed bizarre.

That said, I have now worked in a number of academies run by a number of sponsors, and I have enjoyed my time in them. I do think, however, that this has been down to those in charge. I have heard from friends in other chains that staff welfare is low in the priority list, that staff feel under pressure and that they feel their pay and conditions have suffered detrimental effects since academisation.

In my last role I was a union representative at a time when Gove was tearing up the burgundy book, introducing PRP and generally going to war. The unions were concerned about the particular academy chain we were part of and issued guidance on which specific policies we should reject. They didn’t come, after a while we arranged to meet the head to discuss,  the meeting was short and pointless really as we expressed our concerns and we’re told “I know, I couldn’t believe they expected me to implement those policies so I’ve sent them back with my views made clear and I’m waiting for their response.” It made me very thankful to have her as a head, but also worried a little about colleagues in other schools in the chain. The other sponsors I’ve worked for have been 2 and 3 academy trusts and they seen much better, but again I wonder how much the principals have protected us from.

In general, some academies and free schools are run ethically, with student and staff welfare at their heart but not all are. And that is still a major worry for me. Surely all schools should be subject to the same rules, the same regulations and the same protections.

Formative Assessment

May 5, 2015 2 comments

My current MA assignment is on Formative Assessment and as you might imagine the topic has been at the forefront of my mind recently. It’s a topic I’ve touched on before, and one I’ve wrestled with throughout my entire career.

When I was a trainee teacher I heard the term AfL constantly, I knew it stood for “Assessment for learning”, but I knew very little else.  I remember being shown a video of Dylan Wiliam running a classroom experiment where they removed grades from marking and replaced hands up questioning with lolly sticks. An interesting video, not least because the top achieving girl stole the stick with her own name on!

During my teaching placement I heard on more than one occasion “you need more AfL, use lolly sticks or whiteboards”, I heard comments like “that’s a good card match, and it covers your AfL”, once I heard “get them standing up to cover your AfL”. None of this helped. I still managed to finish my PGCE with only a slim grasp on what AfL even was.

Similarly, my NQT year started without any real ideas, but I started to get to grips when my mentor discussed mini whiteboards and how she’d seen people not use them properly, having pupils wave them as soon as they have an answer. I began to realise their use, and gain a better understanding.

As time progressed I became more reflective and I began to think more about the formative assessment I used. I realised that even though I was doing the assessment right, ensure whole class answers were shown together etc there was no point, as it didn’t affect what I was doing. I was using whiteboards to check understanding but teaching the lesson the same. To be effective, surely the plans have to change.

This realisation rocked my perception a little. Up until this point I had thought that ensuring lessons were thoroughly planned was they key. I now realise that willingness and ability to divert from those plans is. If the students can all do, without prompting, the subject of the lesson when it starts, there’s no point teaching them. But similarly, there’s no point moving on after they’ve done something once as they will not retain that information. Formative Assessment must be constant and effect the lesson, you should be checking baselines, checking they have the skills and knowledge to attempt a task, checking they are practising those to ensure retention.

The same principles apply to written feedback, the longer it goes the more useless it becomes. If you mark every two weeks, at the end of a topic say, and a learner has picked up a misconception you have missed in lesson 1 then there’s a strong likelihood that there’s going to be an issue all through. That’s why checking work in class, as it’s being completed, is imperative. That way you can catch the issues as they happen and correct them on the spot.

There’s a lot of research and writing out there on Formative Assessment, and currently I’ve only just brushed the surface, but I’m adequately intrigued to see what others have said.

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