We need "much more assessment" of the "right kind" in primary schools, the adviser who chaired the last national curriculum review has said.
Speaking at today's Westminster Education Forum on primary assessment, Tim Oates, from Cambridge Assessment, also said he believes that the Reception baseline assessment (RBA) is an "important" experiment that has been developed and introduced "in the right way".
"In science, where we removed testing some years ago, we've fallen in Timss [the Trends in International Mathematics and Science Study] back to the standards of the 1990s in terms of measured attainment," he said.
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"Now, I think the absence of good assessment, which feeds back into learning, is part of that picture in science, in primary. It's really a critical issue for us, I think as a nation.
"I think we need much more assessment, but I mean we need much more assessment of the right kind."
Backing for Reception baseline assessment
He added: "We must not forget the curriculum principles of the new curriculum, which was introduced in 2014 – not so new now, but still a newish curriculum across the whole of the system.
"Those principles were: fewer things in greater depth; a system of learning, which pupils own for the rest of their lives – not things that they have briefly experienced, recalled for a test and then forget – because that constitutes personal capital.
"And nothing is as good as a good question. They stimulate thought, they excite curiosity, and they tell us about the mental life of each child.
"And if we use those criteria, those principles, to develop high-quality assessment in primary and in the rest of our education system, we will see continued improvement in attainment and improved equity."
On the RBA, Mr Oates said: "I think the baseline test has been developed and introduced in the right way, and is contributing to us having much more assessment of the right kind.
"I think this could seem to be quite a polarised debate. I think we are undertaking a very, very important almost experiment with the baseline test.
"I mean, we are trying to get something in place...which does provide the state with the necessary information it needs to see the spread and texture of attainment and equity in the education system.
"We know that getting an early sight of that, and not leaving it to the age of 11 or the age of 16, is important.
"And if we can ensure the test does...have collateral benefit in its application, we might get the balance we require. I think it's tricky, but I think we've made good steps so far."
He added: "One of the things that I would commend about the way in which the baseline test has been developed in the UK, is that the process of development has been jointly negotiated and undertaken with the profession, and the professional associations have been involved and consulted upon and made their contributions.
"I don't think we should forget that – it's been, I think, an exemplary process."