Tyree Wilson, 12, of San Leandro, Calif., practices using his spacer and inhaler to treat his asthma on the Breath Mobile Thursday, Sept. 20, 2012 at
Tyree Wilson, 12, of San Leandro, Calif., practices using his spacer and inhaler to treat his asthma on the Breath Mobile Thursday, Sept. 20, 2012 at Woodrow Wilson Elementary School in San Leandro. (Alison Yin/For Bay Area News Group) ( Alison Yin )