The teacher in question referred to friends daughter (Year 4) as 'bonny'. I realise that there are areas of the country where this is just a compliment without any other connotations but here it essentially means 'fat.'
The friends DD was a few minutes late due to helping set up the assembly and upon entering had gone to sit with her friends and was stopped by the teacher who tried to steer her to the year 6s and when she politely explained she was in year 4 the teacher commented (in a whole school assembly where the children could all hear her) 'well, you are a very bonny girl for year 4, aren't you?'
Not the teachers finest hour, I don't think?