Research shows that pupil numbers in the two countries had increased by similar proportions between 1994 and 2001 but at less expense over here.
Philip Stevens and Mary O'Mahony at the National Institute for Economic and Social Research, found this was because of the increasing use of teaching assistants in UK schools.
Mr Stevens said: "This means that the UK is getting more for its money. Yet this stands in direct contrast to labour productivity growth in the total economy in both countries, for example American car manufacture or banking is far more productive than here.
"But in education we are achieving an expansion in the number of students, particularly in higher and further education, at a lower cost in terms of labour input, as compared to the US.
"One explanation for this is the increased use of auxiliaries, such as teaching assistants. Although the numbers of staff in UK education have risen at a similar rate to those in the US, the majority of this increase has been made up of auxiliary staff."
The paper, among research by economists on education and training in the UK, was presented at the annual conference of the Royal Economic Society.
Other studies included research on the economic disincentives and incentives for becoming a teacher.
The study by Tsung-Ping Chung, at the London School of Economics and professors Peter Dolton, at Newcastle university, and Andrew Tremayne, at York university, said that a 10 per cent wage rise was likely to reduce the rate of teachers leaving the profession by 1,700 women and 616 men a year.
In 2001-2, 14,760 women and 5,720 men left the profession.
They also calculated a 10 per cent rise in graduate unemployment would be likely to lead to a 2.5 per cent increase in graduates opting for teacher training.
Research by Steven McIntosh from the LSE showed that young school-leavers can catch up with their higher-achieving classmates if they go on to vocational education. He said acquiring a level 3 national vocational qualification raises the likelihood of employment to the same level as someone leaving school with A-levels.