The Guardian reports that Sutton Council is spoiling for a fight with Education Secretary Michael Gove over its plans to raise the cap on primary class sizes to more than 30 pupils.  The Chief Executive of Sutton Council Niall Bolger is reportedly contacting other local authorities to test support for raising primary school class sizes.  It's been driven by the massive boom in demand for primary school places across London as the number of primary pupils soars by over half-a-million between 2010 and 2018.  Councils are already building mobile class rooms to cope with the squeeze.