Council members approved the project at Base Line Road and Mountain Avenue, which is close to the 210 Freeway, despite concerns about the health impacts that young and old residents may have to deal with.
The project includes 54 detached residential condominiums.
"There's one major serious thing we need to address, which is the emerging air quality consensus that it's not good to put such communities so close to the freeways," resident Ranji George said.
"They found out in studies in Europe and here that those who live near the freeway, within 800 feet of it, have a 350 (percent) increased chance of cancer over a lifetime. That's serious in the sense it affects younger infants to children to senior citizens."
Councilman Opanyi Nasiali was the lone councilman who agreed with George's concerns about the project.
"If people live here for 70 years and especially if (they're) kids, I'm very concerned about the study that concludes kids are really impacted by air pollution for the freeways," Nasiali said.
"Even though we are putting in a mitigation measure in the building, kids are going to play outside and are going to be exposed to the pollution."
Councilman Joe Lyons said he was satisfied that the project considered air quality issues and would create a workforce living in Claremont "without having long commutes and contributing to the air pollution that comes from that transportation source."
Home builder D.R. Horton put in a winning bid of $6.2 million for the 4.35-acre piece of school district property at 2080 N. Mountain Ave.
The site formerly housed the Claremont Unified School District offices.
Of the 54 detached residential units, there will be eight for sale at moderate-income housing.
D.R. Horton, vice president of entitlements Daniel W. Boyd, said the "market rate" for the residential units would be $400,000, while the moderate-income housing rates would be from $250,000 to $280,000.
The council recently approved a conditional use permit for the project by a 4-1 vote.
The next step for the project was an architectural commission meeting to review home designs tentatively scheduled for March 13, said Brian Desatnik, housing and redevelopment manager for Claremont.