Posted 2nd April 2018

Since White Rose Maths began creating questions for Diagnostic Questions last year, there have been 2,721,752 answers to White Rose Maths questions given by students all over the country. Perhaps more importantly, 1,012,072 of these answers have been incorrect.

So, with SATs on the horizon, I thought it would be a perfect time to reflect on five areas of mathematics that have proved particularly troubling to Key Stage 2 students answering our daily SATs questions - and in another blog I will do the same for Key Stage 1. For each of these areas I have selected a poorly answered question, provided some insight as to where the confusion may lie, and shared a real-life student explanation taken from the site.

A good approach might be to show one of the questions to your students in class, get them to vote with their fingers for the correct answer, have a discussion about both the correct and incorrect answers as described in this blog post here, and then set the accompanying mini 5 question quiz for homework to see if their misconceptions have been resolved. Then repeat for the other four areas.

You can find the complete White Rose Maths collection here, which contains all the Key Stage 1 and 2 daily revision questions and topic-specific quizzes at the bottom of the page. Here you will also find information about our completely free schemes of work that allow you to automate the setting of top-quality quizzes throughout the year.

I really hope you and your students find this useful.

Craig Barton - @mrbartonmaths

**Question link**: https://diagnosticquestions.com/Questions/Go#/32836

**Results:**

A | B | C | D |

21% | 13% | 60% | 6% |

**Discussion:**

The confusion between factors and multiples is a common one. Both answers A and B suggest students are muddling up these two related concepts. This question is made all the more challenging by the fact the correct answer is one of the numbers given in the question. Students’ knowledge of multiples needs to be very secure to get this lovely question right.

**Example student explanation:**

A - “I think that 2 goes into both 4 and 12 as 4 and 12 are both even meaning they are in the twos.We can check this by doing 2x2 and 2x6 as they both get you twelve.

**Follow-up Quiz:** https://diagnosticquestions.com/Quizzes/Go#/50500

**Question link**: https://diagnosticquestions.com/Questions/Go#/33473

**Results:**

A | B | C | D |

23% | 59% | 7% | 11% |

**Discussion:**

This question catches out any student who does not pause to think. Answer A suggests students have seen 20%, seen 60, and just assumed they are being asked to work out 20% of 60. Answers C and D are also interesting, implying students may have spotted the correct method to use, but were then let down by their arithmetic skills.

**Example student explanation:**

A - “Finding 20% of a number is the equivalent to dividing a number by 10 then multiplying it by 2. So, I did this with 60. 60 divided by 10 = 6 and 6 x 2= 12 and that is how I got the answer of 12.”

**Follow-up Quiz:** https://diagnosticquestions.com/Quizzes/Go#/50503

**Question link**: https://diagnosticquestions.com/Questions/Go#/32828

**Results:**

A | B | C | D |

19% | 11% | 58% | 12% |

**Discussion:**

Here we have another example of students confusing two related concepts, this time area and perimeter. Answer A has lured in any students who failed to make that distinction. Interestingly, students answering B may have a sense that perimeter is to do with adding, but have failed to account for the other two sides. Students answering D may be guessing based on the diagram, or made an arithmetic error during the division.

**Example student explanation:**

A - “I know to find the perimeter you need to times length by width I also know that the perimeter of the rectangle is 24 cm ; 3 is in my multiple choice and I know that 8 x 3 = 24 so I now know what the width is.”** **

**Follow-up Quiz:** https://diagnosticquestions.com/Quizzes/Go#/50504

**Question link**: https://diagnosticquestions.com/Questions/Go#/33470

**Results:**

A | B | C | D |

14% | 10% | 38% | 38% |

**Discussion:**

This is one of my all time favourite questions, because each answer clearly reveals a different misconception, and to get this question correct students must be secure in more than one area of mathematics. Answer C suggests students have ignored the inequality sign and just made the two fractions equivalent. Answer A implies students have spotted that a multiplying factor of 5 has been used on the numerators, whereas students choosing answer B may understand the inequality sign but not know how to order fractions. A great question!

**Example student explanation:**

C - “I think it is this answer because you work out how many 4's go into twenty and that is 5. So with fractions whatever you do to the top you do to the bottom. Now you divide 5 by 35 because it is the same as saying ?×5=35. Once you have got your answer I can assure you it will be the right one.”** **

**Follow-up Quiz:** https://diagnosticquestions.com/Quizzes/Go#/50508

**Question link**: https://diagnosticquestions.com/Questions/Go#/34576

**Results:**

A | B | C | D |

51% | 15% | 18% | 16% |

**Discussion:**

Another fantastic question for highlighting specific misconceptions that students have. Answer C suggests that students understand that angles on a straight line add up to 180, but have not read the question carefully enough. Answer B implies students have correctly worked out the size of each angle, but have chosen the wrong one. Finally, students who chose D may well be simply going off inspection. Once again, to get this question right, you really need to know your stuff!

**Example student explanation:**

C - “I know the answer is 140° because angles on a straight line total 180°. I need to find out how much the larger angle is and I know it is 40° larger than the smaller angle of B so if I take 40° away from 180°(the total) I will get my answer of 140° (C)”

**Follow-up Quiz:** https://diagnosticquestions.com/Quizzes/Go#/50509