Kids at the da Vinci School learn that red and blue aren’t the only colors that save the world. In addition to having a science-based curriculum, the private preschool and kindergarten will soon be completely “green.” Mary Ann and Stan Greene, owners and directors of the school near Central Expressway and Walnut Hill, are constructing a new building at Midway and Royal to make the school entirely environmentally friendly, from a previous pavement to a playground ferris wheel that initiates irrigation. Mary Ann Greene says it’s important to “plant seeds of other ways of living in the world a little more gently.” She practices what she preaches by forgoing the traditional goldfish-type snacks for non-processed options and asking children to dump their lunch remains in each classroom’s compost pile, where wriggling earthworms break it down. The new building will take the Greenes’ philosophy to the next level, generating power naturally by way of a wind turbine and certain elements of the playground. The cost of constructing a green building as opposed to a standard structure is only 1 to 2 percent higher, Stan Greene says, but the long-run savings exponentially exceed that of any conventional building.