Plans to attract higher-quality recruits into teaching in England have been set out by the government.
Tougher rules to enter teacher training are to be introduced, including limits on the number of re-takes for tests in numeracy and literacy.
There will also be bursaries of up to £20,000 to attract students with first-class degrees in priority subjects.
"We need to attract the best people to train to teach," said Education Secretary Michael Gove.
"We have some excellent teachers in this country, but many who could make a huge difference in the lives of children choose other professions," he said.
But head teachers' leader Russell Hobby said you would not attract top candidates by cutting teachers' pensions.
"Worrying about entry tests is somewhat ironic in the face of the largest threat to teachers' terms and conditions in decades," said Mr Hobby, head of the National Association of Head Teachers.
The education secretary has said persuading the most talented students to enter the teaching profession is an important part of raising standards - high-achieving school systems such as Finland and South Korea recruit teachers from the top 5% to 10% of graduates.
As such Mr Gove wants a recruitment system in England that encourages applications from high-achieving students.
For trainees entering in 2012 there are proposals for financial incentives on a sliding scale of between £20,000 and £4,000 for a one-year postgraduate course.
The highest bursaries of £20,000 will be for students with first-class degrees who would teach physics, maths and chemistry in secondary school.
In medium-priority subjects, such as modern languages, students with a first-class degree would receive £13,000. For primary or other secondary subjects, they would receive £9,000.
A modern-languages trainee with a 2:1 degree would receive £10,000. A trainee teacher for primary school would receive £5,000 with a 2:1 or £4,000 with a 2:2.
This is against a background in which teacher-training students will be paying higher tuition fees of up to £9,000 per year.
There will also be a fund to protect teacher-training courses, which might no longer be financially viable under the changes in higher education funding.
There will not be any bar on teachers with third-class degrees - but they will not have government funding.
There will also be an attempt to filter out weaker candidates by only allowing teacher-training applicants to fail numeracy and literacy tests three times.
At present students are allowed to take unlimited re-sits while they train.
The numeracy tests include graphs and tables, as well as mental arithmetic questions using percentages and fractions.
There will also be an emphasis on teacher training in schools, with outstanding schools or groups of schools being designated as Teaching Schools, where trainees can learn at first hand.
The first wave of 100 such Teaching Schools are expected to be running in the autumn.
NAHT leader Russell Hobby agreed that there should be high standards for those entering teacher training.
But he warned against putting too much emphasis on high degree grades.
"We should not fall into the trap of thinking that academic excellence necessarily makes someone a great teacher.
"We want smart people, but we also want visionary, caring, energetic, creative and thoughtful people. The proposals neglect inter-personal skills. And they implicitly neglect primary and early years," said Mr Hobby.
Pam Tatlow, chief executive of the Million+ group of new universities, which includes teacher training institutions, questioned the link between degree grade and teaching ability.
"A first-class honours degree is not in itself a passport to becoming an effective teacher.
"It is also difficult to see how this will broaden the profile of those becoming teachers."