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Try to answer the following questions here:

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Checkpoint description

Describe what's changed since the last checkpoint.

Picture of Christian Lawson-Perfect

Christian Lawson-Perfect 4 months ago

Saved a checkpoint:

Replaced string restrictions with pattern restrictions.

Restore this checkpoint

Elliott Fletcher 2 years, 1 month ago

Published this.
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Christian Lawson-Perfect 2 years, 2 months ago

Gave some feedback: Ready to use

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Christian Lawson-Perfect 2 years, 2 months ago

Saved a checkpoint:

Looks OK.

You had the expected variables set incorrectly for the last two parts. You should just give the single variable names you expect, not combinations of them. And the whole point was to give a warning when the student types xy, not allow it!

Restore this checkpoint

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Bradley Bush 2 years, 2 months ago

It isn't worth fixing the x*( issue so we have left it

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Bradley Bush 2 years, 2 months ago

Gave some feedback: Needs to be tested

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Bradley Bush 2 years, 2 months ago

Gave some feedback: Doesn't work

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Bradley Bush 2 years, 2 months ago

Thank you for the advice, I've removed 1 as a variable and I had added expected variable names but I've now added warning messages, although I have run into another problem with x*( being required overriding this message, so I'm going to need to ask how to change that.

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Christian Lawson-Perfect 2 years, 2 months ago

Gave some feedback: Has some problems

Picture of Christian Lawson-Perfect

Christian Lawson-Perfect 2 years, 2 months ago

In part a, when a[1]=1, I didn't get any brackets. Either make sure it's greater than 1, or turn off the unitFactor rule.

You need to give feedback messages for the string restrictions. "It doesn't look like you've expanded - make sure you don't use any brackets in your answer" would do.

Did you try adding expected variable names to the parts?

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Bradley Bush 2 years, 2 months ago

Gave some feedback: Needs to be tested

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Bradley Bush 2 years, 2 months ago

Thankyou for the advice, I've added string restrictions, moved the answer boxes and i've added brackets to the advice. Although I haven't added fullstops on the end of questions because they're lone 1 line equations with no sentence sturctured around them 

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Bradley Bush 2 years, 2 months ago

Thank you for the feedback, I have fixed the string restrictions on all the parts, I've added the gap boxes and I've put more brackets into the advice but I haven't added the fullstops because the questions are one line and nowhere near a sentence, I'm not sure it's needed.

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Bradley Bush 2 years, 2 months ago

Gave some feedback: Needs to be tested

Elliott Fletcher 2 years, 2 months ago

Main Parts

parts a) and b)

Typing in the correct answer works fine, but it also displays the red exclamation mark warning saying "Your answer was interpreted to use the unexpected variable name x". This doesn't appear for any of the other parts, so i would maybe take it out.

For all parts, i would put the answer box on the same line as the question, for example

8x(-3x-3x^2+2) = -24x^2-24x^3+16x.

I think it just looks a bit neater.

Parts i) and j)

I would give a hint for students to use the * when writing a product of two different terms like xy in the answer box, in case some students write this and can't understand why their answer is wrong. I think this can be done in the string restrictions section.

I'm not sure how important this is, but maybe put a full stop at the end of each question (after the answer box), also in the advice section.

Advice

I think there should be brackets around the terms that you are multiplying together (even though i know the point of this question is to expand brackets), for example for part a)

\[
\begin{align}
10(-4x-9) &= (10 \times -4x)+(-9 \times 10),\\
&= -90-40*x.
\end{align}
\]

Elliott Fletcher 2 years, 2 months ago

Gave some feedback: Has some problems

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Bradley Bush 2 years, 2 months ago

Gave some feedback: Needs to be tested

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Christian Lawson-Perfect 2 years, 2 months ago

Gave some feedback: Has some problems

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Christian Lawson-Perfect 2 years, 2 months ago

Very nearly there!

Add restrictions to the parts forbidding brackets, to make sure the student has expanded in some way. It'll be too much effort to make sure they've collected like terms in the later parts.

In the parts with more than one variable, make sure you set the "expected variable names" field, so that mistakes like typing ab instead of a*b get caught.

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Bradley Bush 2 years, 2 months ago

Gave some feedback: Needs to be tested

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Bradley Bush 2 years, 2 months ago

Thank you again for the feedback, I see what you mean with the statement, and again I am really sorry about the typos. I had changed the statement before but hadn't considered including the simplest form part in it. I am slightly worried that now without any text to preface the questions, the question is looking a bit boring, I'm not sure if there is anyhting I should be writing inbetween questions that you could suggest? 
As for every other question being the same, did you note that the random variable can be both negative and positive. I thought negativity could be a tripping point for someone struggling with expanding brackets, so it would be good to include two versions of each, that way the student wouldn't be put off by a greater variety of the same question? Might it be worth constructing it so that every other example includes negative numbers so they come up less randomly? 

Vicky Hall 2 years, 2 months ago

Gave some feedback: Has some problems

Vicky Hall 2 years, 2 months ago

I agree with Christian that a better statement would be:

Expand the expressions below by multiplying each of the terms inside the brackets by the term outside. Give each answer in its simplest form.

Having the 'simplest form' prompt in the statement will save you having to repeat it in every part of the question. 

The questions get progressively more difficult but you essentially have two of each question, which seems unnecessary and makes the page look very long. If a student really wanted to do a particular type of problem multiple times, they could just refresh the page.

Have a check that your advice headers are in heading 4. There are also some typos in the advice.

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Bradley Bush 2 years, 3 months ago

Thank you for the feedback, I have now acted on the comments you gave by chaning all the questions into the mathematical expressions format, adjusting the variable sizes to make the mental maths easier and trying to make both the question statement and the advice more straight forward.

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Bradley Bush 2 years, 3 months ago

Gave some feedback: Needs to be tested

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Bradley Bush 2 years, 3 months ago

Saved a checkpoint:

before removing the gap fill

Restore this checkpoint

Picture of Christian Lawson-Perfect

Christian Lawson-Perfect 2 years, 3 months ago

Gave some feedback: Has some problems

Picture of Christian Lawson-Perfect

Christian Lawson-Perfect 2 years, 3 months ago

The question statement is a bit of a run-on sentence. Try something like:

Expand each of the expressions below. 

Multiply each of the terms inside the brackets by the term outside the brackets.

One of the GCSE textbooks might have a good formulation of this prompt that you can use for inspiration.

Why have you made your own part headers instead of splitting each expression into its own part?

Think about the difficulty curve for these problems: you should start with a very simple example, and slowly add more complicated elements, one at a time. So you might start with $2(x+1)$, then follow that with $x(x+1)$, which requires multiplying $x \times x = x^2$. Think about how games do this: you begin with very simple challenges while you get used to the controls, then more elements are added in as you become more secure in those.

While randomised numbers are good, this question is about algebra so maybe restrict coefficients to single digits. I don't know my 17 times table! Don't let students fail for the wrong reason: a mental arithmetic error is a distraction here.

The advice is written in the passive voice: "Brackets are expanded by..." Give a concise explanation of what "expanding brackets" means - you multiply terms so that no brackets are left - and then give a few generic examples, such as $a(x+2) = ax + 2a$.

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Bradley Bush 2 years, 3 months ago

Gave some feedback: Needs to be tested

Bradley Bush 2 years, 3 months ago

Created this.
Name Status Author Last Modified
Expansion of brackets Ready to use Bradley Bush 16/05/2019 17:08
haken met distributieve eig uitwerken draft Johan Maertens 12/09/2018 16:06
spørsmål 1 draft Ida Landgärds 02/05/2018 08:52
spørsmål 1 draft Ida Landgärds 20/06/2019 09:34
Ida's copy of spørsmål 1 draft Ida Landgärds 30/08/2018 11:26
Angharad's copy of Expansion of brackets Ready to use Angharad Thomas 26/10/2018 13:38
Maria's copy of Expansion of brackets draft Maria Aneiros 29/05/2019 05:59
ahmad's copy of Expansion of brackets draft ahmad yahya 30/05/2019 11:27
Øystein's copy of Expansion of brackets draft Øystein Hildre 12/06/2019 09:04

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