More than half a billion pounds is to be pumped into creating new free schools, including grammars and refurbishing existing school buildings, the Government has said.
Wednesday's Budget will include £320 million to help fund up to 140 new schools, creating 70,000 new places.
However, critics of the plans have accused the Government of "throwing money at free schools and grammar schools," adding that £6.7 billion was needed just to bring all existing school buildings up to a "satisfactory" level.
The investment is intended to build on the Government's commitment to open 500 new free schools by 2020, Chancellor Philip Hammond will announce on Wednesday.
The move follows on from the Prime Minister's pledge last autumn to create a place at a good school for every child, in part through allowing selective schools to expand and new ones to open.
However, Theresa May's controversial announcement attracted widespread criticism, with opponents arguing that expansion would lead to segregation and a two-tier education system.
It is not thought the Government has set a target on the number of grammar schools it wants to open with the new funding, but it is open to selective institutions submitting proposals.
The money includes funding for more specialist maths colleges, such as the existing Exeter Mathematics School - which selects 16 to 19-year-olds based on their aptitude for the subject.
Of the 140 new free schools, 20 will open by 2020, and the majority of the rest will open over the course of the next parliament.
There are currently 431 open free schools - a key plan of Conservative education reform - and a further 243 in the process of opening.
The Budget will also include a further £216 million to rebuild and refurbish existing schools in England, to ensure that they are fit for purpose.
This money is on top of existing plans to spend more than £10 billion on school buildings over the course of this Parliament.
The current entitlement for children who access free home-to-school travel is to be expanded to cover selective schools.
Ms May said: "For too many children, a good school place remains out of reach, with their options determined by where they live or how much money their parents have.
"Over the last six years we have overseen a revolution in our schools system and we have raised standards and opportunity, but there is much more to do.
"As part of our commitment to creating a school system that works for everyone, today we are confirming new investment to give parents a greater choice of a good school place for their child, and we will set out the next stage of our ambitions in the coming months."
Mr Hammond said: "Investing in education and skills is the single most important thing that we can do to equip our children for the future.
"We are not starting from scratch; we have protected the core schools budget, which stands at over £40 billion this year, and these announcements take the next steps in giving parents greater choice in finding a good school for their child, whatever their background."
In expanding the free schools programme, the Government said it is aiming to target the one million children at under-performing schools.
The funding announcement comes just weeks after a spending watchdog warned that the Government is pouring billions into building new free schools in England while existing state schools are crumbling due to lack of repairs.
The National Audit Office (NAO) said £6.7 billion was needed just to bring all existing school buildings up to a "satisfactory" standard, with a further £7.1 billion required to restore them to a "good" condition.
But with ministers committed to creating 500 new free schools by 2020, the NAO said the Department for Education (DfE) was facing an estimated bill of £2.5 billion by 2022 simply to purchase the land needed to build them.
It added that while free schools were helping to meet the demand for additional school places in some areas, because local authorities did not control their numbers they were not necessarily "fully aligned" with their needs.
Shadow education secretary Angela Rayner said: "Over half a million children are stuck in oversized classes because this Government has failed to ensure there are enough school places.
"Free schools are still being opened in areas where they are not needed and where there is no demand for them. This is now throwing more good money after bad. It will do nothing to address the shortage of available school places.
"The Tories are breaking their manifesto promise to protect per-pupil spending, and this Budget was a missed opportunity for them to right this wrong. Schools are still facing £3 billion cuts and children all across the country are paying the price for Tory failure."
Dr Mary Bousted, general secretary of the Association of Teachers and Lecturers, said: "Teachers and heads in the thousands of existing state schools in the UK which are facing real-terms cuts in funding for their pupils will be dismayed to see the Chancellor throwing more money at free schools and grammar schools.
"It will do nothing to help schools recruit and retain teachers and heads, and will put a broad and balanced curriculum at risk."