Our teacher diary follows one maths teacher's journey using LbQ. Duncan Whittaker at [St Christopherâ€™s Church of England High School](http://www.st-christophers.org//) gives us a snapshot of its application and its impact in these regular updates.
### ![alt text](/filestore/BlogImage/f8ec82cb-3c55-4469-ac7b-bfa70edd8a55/58a17718-a6a3-4bb9-948a-c5ede219badfDuncanPicEdit.png "Duncan")
Class 9.4 - the students in this class are lively and they respond with great enthusiasm towards Learning by Questions. The average estimated class grade for the end of year 11 is grade 3.
## 7th January 2019
Aim of the lesson: consolidate studentsâ€™ understanding of denominators using [Add and Subtract Fractions with the Same Denominator](http://www.lbq.org/Questions/UserQuestionSetPreview/Add-and-Subtract-Fractions-with-the-Same-Denominator/) Question Set.
Length of session: 19 minutes 43 seconds
Number of students: 15
Number of answers: 379
Answers right first time: 72%
## Learning by Questions lesson overview
I wanted to establish the fact that the denominator does not change with this bottom set class - instead of just skimming through it quickly, I thought it would be best to fully establish this understanding. In the Add and Subtract Fractions with the Same Denominator Question Set, the reasoning and problem solving questions looked really good and I decided to run the full question set instead of adapting.
## Teacher intervention
![alt text](/filestore/BlogImage/f8ec82cb-3c55-4469-ac7b-bfa70edd8a55/cedfcc4b-ddb7-4184-9fe6-25f1bc0a05faMatrix-Blog1.JPG "")
### Q3. 1/4 + 1/4 = ____
Students J and H* had been using \ instead of /.
### Q16. Dan eats 2/8 of the pizza and Shelly eats 3/8. What fraction of the pizza do they eat in total?
L thought that 6/8 + 6/8 was 12/16. I asked him "What is the most important point from today's lesson?" He said, "the denominator does not change." The penny dropped.
### Q17. Pippa subtracts three-fifths from four-fifths. What answer does she get?
This question asks students to answer the question using words. This caught a few pupils out as they did not read the question carefully enough. They typed in the fraction and not the words. A useful question to improve literacy.
###Q24. 3/8 of children in the school are boys. What fraction are girls?
E put her hand up for assistance. I asked E what the "1" represents. She said "one whole one". I asked her how many sevenths were in one whole one. She replied "I do not know." I asked her how many halves make a whole one? She said 2. I repeated the question: How many sevenths make a whole one? She said 7. The penny dropped.
###Q27. Victoria spills some ink on her work and can't see the answer. What number has been covered in Victoria's answer?
E put her hand up for assistance. I had to ask her how many sixths were in one whole one, and then how many sixths were in 2 whole ones. Then penny dropped for E. However, the rest of the class could not answer this question and time was running out. I asked a quick ad-hoc question but the feedback showed me that they still could do this - tomorrow's lesson shall start here.
**Summary**
**Stay tuned for the next instalment of Teacher Diary with Duncan Whittaker. In the meantime, if you would like to try out Learning by Questions in your classroom, [open your free account](http://www.lbq.org/Register/) and take advantage of all our Question Sets for free.**
*Real student names have been omitted.