About a third of the preliminary budget proposed by Mayor Bill de Blasio on Tuesday would go to the public school system. He is proposing to spend more on buildings, crossing guards and faster internet service while cutting spending on services for homeless students. Our education reporter, Lindsey Christ, looks at his proposal.

It's an economic issue, Mayor Bill de Blasio said, proposing a $24 billion operating budget for the public school system.

"You hear this from folks in the business community all the time in terms of decisions to build a business, start a business, relocate a business, it comes down to the quality of schools," de Blasio said.

The Mayor's spending proposals reinforce his long-term priorities — $6.3 million for new school crossing guards, an effort to reduce pedestrian deaths; $23.6 million for faster internet, key to his promise to have every student studying computer science; and $14 million for a new second-grade summer school program.

"As one of the ways we supercharge our efforts to achieve that goal of all kids reading by third grade," De Blasio said.

But there are cuts, too.

The Mayor proposes to slash funding for homeless students, even though that population is at a record high — more than 105,000 students were homeless at some point last year, one in every ten children.

Just last month, his schools chancellor touted  $30 million in new spending to help homeless students, including placing teachers in shelters. However, the mayor's new proposal would reduce that by $10 million.

Asked about the cut, de Blasio suggested reforms to the shelter system could create savings.

"For example if we get a lot of kids closer to their home districts or in their home districts, that is going to take — thank God — less school busing."

But he said there is time to restore the cut before a final budget is adopted.

The re-election-minded mayor also highlighted his proposal to spend another half a billion dollars to build schools accommodating another 38,000 students.

"A big deal to a lot of parents, it’s been one of the issues we hear the most about, I hear most about," De Blasio said.

However, that spending is for the capital budget that begins in July 2019 more than two years, and one mayoral election away, meaning it is not ironclad

And it take would years to ease the overcrowding — and reduce the large classes — that exist in many parts of the system right now.