The digital counter ticked down the remaining minutes of Ignacio Mesa Viera’s dialysis treatment.

At Esparza’s Jewelry in the Fruitvale section of Oakland, the owner, Rodolfo Perez, works the counter with a .38-caliber revolver strapped to his belt.

If the residents of the Haight, the Castro, the Mission and other San Francisco neighborhoods were given a giant public chalkboard, what would they write?

Grant Gordon knows — thanks to his 2001 Toyota Echo.

Every perceptive teacher sees a diversity of strengths and weaknesses in each of her students: There is the child who loves math but has trouble playing well with classmates, the one who makes friends easily but struggles to stay focused on written tasks, and another who creates beautiful paintings but can’t seem to retain much of what she’s read.