Salazar Elementary receives new playground, trees and mural as part of ‘Cool School’ program Six schools in Dallas received outdoor upgrades including a new playground, loop trail, outdoor classroom, art mural and up to 100 newly planted trees. Exterior view of the Dallas ISD Administration Building on Monday, April 6, 2020, in Dallas.(Smiley N. Pool / Staff Photographer) Oak Cliff’s Salazar Elementary is one of six Dallas schools that has received outdoor upgrades. As part of its Cool Schools program, Texas Trees Foundation partnered with Dallas ISD, Dallas Parks and Recreation and other organizations to build new community outdoor spaces at six elementary schools located in the nonprofit’s designated Cool School neighborhoods.