Teachers participating in the first wave of Mayor Bill de Blasio’s “Algebra for All” initiative will have access to a new online forum to talk about instruction and more planning time, education officials announced this week.

Though the mayor’s program won’t be fully scaled up until 2021, the schools that have signed up to begin offering more rigorous instruction will start that process this fall, according to a memo sent to principals that offered new details about the city’s plans.

Teachers who sign up will receive 20 days of grade-specific training, 10 of which will take place over the summer. Within schools, math teachers will be given at least one common planning period each week. School leaders will also have access to an unspecified number of math-specific training sessions.

Next year is a planning year for the schools testing out the program. But by 2017-18, participating schools must guarantee all eighth graders the option to take algebra, and ninth grade Algebra 1 students must get at least five hours a week of math instruction.

You can find a complete rundown of what resources the first batch of schools participating in the Algebra for All will receive here – as well as what programmatic changes schools will be required to make.

Seventy-five schools are participating in another branch of the Algebra for All program to “departmentalize” math in fifth grade. It is unclear how many schools will sign up for the middle and high school branches of the program.

The logic behind increasing access to algebra, according to the city, is that research shows students who pass the subject by the end of ninth grade are more likely to graduate high school and college. Students won’t be required to take algebra earlier, though, a policy that some other cities have found problematic.