Pupils in P1 complete two separate tests – one in numeracy and one in literacy – at appropriate times in the school year.
They are designed to gather information on the children’s abilities and help teachers adapt learning.
MSPs voted by 63 votes to 61 in September 2018 for the Scottish National Standardised Assessments (SNSA) to be scrapped for P1 pupils.
However, at least 283,771 tests have been taken by P1 pupils since MSPs agreed for voting to be scrapped, according to freedom of information requests by the party.
The parliamentary vote was not binding for government ministers, although a review into the tests was conducted.
It found the tests should be able to continue – but recommended modifications such as stronger guidance for teachers in how to support pupils during the assessments.
The tests were introduced in 2017 and assess pupils in P1, P4, P7 and in S3.
Mr Rennie said: “Teachers’ unequivocal message is that these pointless tests tell them nothing they do not already know.
“It is a complete waste of time and gets in the way of learning.
“When Boris Johnson tried to give the Westminster parliament the runaround, SNP MPs were filing legal bids and filling up the airwaves about how atrocious it all was.
“Now that it is their own government doing something so profoundly undemocratic, all we hear is silence.”
He has accused the Scottish Greens – who voted against SNSAs in the vote – of abandoning their commitment to halting tests since entering government.
It was part of the Scottish Greens’ 2021 manifesto to scrap testing for P1s.
He added: “These figures are equally damning for the Scottish Greens. They stood with the Liberal Democrats, Labour and the Conservatives in voting for these to be abolished, but now they hide behind the sofa as these tests carry on.”
A Scottish Government spokesperson said: “David Reedy’s 2019 review of Scottish National Standardised Assessments for P1 found that they have significant potential and should continue.
“Recommendations from the review on enhancing assessments and support materials for teachers have since been implemented.
“The assessment approach in Scotland places teacher professional judgment at the heart of the process. SNSAs are a helpful additional source of information for teachers when considering children’s progress in literacy and numeracy.”