Too many lessons are spent with teachers working out problems while children play a passive role, said Lynne Churchman, specialist adviser for schools.
Ms Churchman, an inspector for the Office for Standards in Education, told a conference of maths teachers that they had a "big job" to do in motivating young people to want to do, and enjoy, the subject.
She told 70 delegates at the Ofsted maths conference in Birmingham that pupils needed better teaching in how to use and apply their knowledge through problem-solving exercises.
But teachers, she said, often had low expectations of their pupils and did the work for them.
This, she added, might explain why in secondary schools in particular standards were "stagnating" with the rate of GCSE A*-C passes now at a "stubborn" 50 per cent.
Ms Churchman said that as a result too many young people leave school without good maths qualifications and carry their negative perception of the subject into adulthood.
She added: "The correct balance must be that pupils do at least as much work and mathematical thinking as their teachers."
Ms Churchman said that during visits to schools when she asked youngsters what they were doing, they often said they did not know and were waiting for the teacher to tell them.