Schools found it tough to make time for art, history and social studies, because of the pressure to focus on core national standards skills.
Mrs Taylor, of decile 9 Lynmore School, said her school's afternoon programme was heavily practical because "some kids have absolutely had enough of reading and writing and maths by lunchtime".
"How miserable would their day be if they just did that all day."
Measuring national standard results had also "soaked up a lot of teacher time", she said.
An Education Ministry-commissioned report in September found teachers' use of the standards last year lacked dependability, ranking children's reading, writing and maths correctly only about 60 per cent of the time.
Professor Thrupp said there was a need for immediate change in the policy to help students and teachers because national standards assessment was becoming too dominant.
The New Zealand Educational Institute commissioned the Rains report.
President Judith Nowotarski said the rigorous research presented indisputable evidence national standards were damaging primary school education.
"For us, key findings are that already national standards have started to have a negative impact on primary schools and the teaching of children - despite the best intention of staff to continue to provide a rich and creative curriculum for children."
Time spent measuring, testing and assessing standards was taking teachers away from real teaching and learning, and other vitally important areas of the curriculum were given less attention, she said.
"We know that subjects such as science, for instance, will be vital for the economy yet national standards do not encourage any focus on that subject.
"But overall, an important principle to remember is that not all children learn the same way or progress at the same rate, or at the same time, so it is totally wrong and misleading to place an arbitrary measure at a particular point in a child's age and say they are failing if they do not meet a certain point at a certain time."