Seventeen years ago, Letty Gali arrived at a fourplex in the community of Placentia to help a family whose son was falling behind in school and being courted by local gangs. It was a Tuesday, and when she arrived, she found a run-down complex and a gaggle of kids playing ball at the end of the cul-de-sac. Most of them were in middle school or close to entering high school and about to face the next chapter of their young lives. In a neighborhood strife with gangs, parents who didn’t have time, and a school system that left kids behind,…