The amount of unpaid overtime teachers clock up means they work for nothing up to every March 22. A report by the Trades Union Congress reveals they'd earn an extra pound;10,000 annually if paid overtime. An Office of Manpower Economics study shows that male primary teachers earn pound;78 a week less than they would in the private sector. Male secondary teachers earn pound;65 a week less. Female primary teachers receive the same as they would in the private sector. Female secondary teachers earn pound;17 more than they would elsewhere.