Last month I shared in **this post**, the work done by Teresa Robinson, who is the Lead Mathematics Adviser for the Russell Education Trust in relation to the Maths that is now in the new Science GCSE and I can now share part 2 (and there is also more to come soon!). I love the idea of having consistent methods across subjects (and the below support sheets are fab!) because it provides an opportunity to reinforce the usefulness of maths in other subjects and its also useful retrieval practice too! The one thing I’d love to see done really well is knowing when other subjects are going to teach specific topics that rely onÂ some form of maths beforehand â€¦ I am sure it can’t be just me that has had a science teacher come up to me and say “tried to teach year 8 *insert something that involves coordinate axes* today and I can’t believe that they couldn’t draw them correctly – what *are *you teaching them in maths?” â€¦ I can’t remember my response but I’m sure it was something suitably sarcastic.

Anyway, I’m ramblingÂ â€¦ so over to Teresa…

This summer I attended the subject network meetings across the Trust for science, design and technology, geography, business and computer science, to discuss the mathematical skills required in each subject and to share the agreed consistent methods for teaching mathematics.

Our consistent methods are not set in stone; if a student successfully applies a method previously learnt then they will be encouraged to continue using this approach, similarly, if a student fails to grasp our chosen methods then alternative approaches are considered.Â

When I met with the GCSE business teachers I discovered that a question on a GCSE maths paper and a question on a GCSE business paper would require exactly the same mathematical working.Â Although using different wording, the questions were in fact asking the same thing, but in a different way.Â For example, in maths the question might be to increase Â£2 by 25%, in business the question might be â€˜A product costs Â£2 to make.Â Calculate how much you would sell it for if you want a 25% mark-up?â€™

Sometimes the wording of the question could be exactly the same in both maths and business.Â For example,

**A machine costs Â£5,000.Â **

**It depreciates by 25% each year.**

**How much is it worth after two years?**

In maths this is called repeated percentage change, in business this is called the reducing balance method.Â The solution below is perfectly acceptable, but is rather clumsy.

**Step 1:** Â Â Â Â Â Â Â Â Â

Decrease Â£5,000 by 25%

25% of Â£5,000 = Â£1,250

Value at end of 1^{st} year = Â£5,000 â”€ Â£1,250 = Â£3,750

**Step 2: Â Â Â Â Â Â Â Â Â **

Decrease Â£3,750 by 25%

25% of Â£3,750 = Â£937.50

Value at end of 2^{nd} year = Â£3,750Â – Â£937.50 = Â£2,812.50

Using bars to illustrate the percentage multiplier, and then using this percentage multiplier produces an efficient solution.

Value at end of 1^{st }yearÂ Â Â Â Â Â Â Â Â = Â£5,000 Ã— 0.75

Value at end of 2^{nd} year Â Â Â Â Â Â Â Â = Â£5,000 Ã— 0.75 Ã— 0.75

Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â = Â£2,812.50

I worked with the Heads of Business across the trust to create student support sheets (PDF version can be found here ->Â **RET Maths in Business (v002**) ) to illustrate the similarities and differences between the two subjects, which are used to promote mathematics skills in GCSE business lessons which I hope you will find useful.

Teresa Robinson, Lead Mathematics Adviser, Russell Education Trust

Zeenat HashimFebruary 8, 2019 at 9:23 amNice!

SCFebruary 8, 2019 at 8:34 pmThis, along with the previous post, is really interesting work thanks for sharing. I am looking into similar and recently asked all Heads of department to audit where they needed to first use Mathematical methods or skills in their subjects so we can compare where we introduce them in Maths. The outcomes were fascinating – standard form for instance in science and DT were needed at various times and different to when we taught it. Now need considering our response from the department. Work like this post sure is inspiration. Thanks.