Children are more likely to shield their faces than to smile when Daniel Santillan points his camera. Santillan's photos aren't for any picture album or yearbook _ they help prove that Mexican youngsters are illegally attending public schools in this California border community. With too many students and too few classrooms, Calexico school officials took the unusual step of hiring someone to photograph children and document the offenders. Santillan snaps pictures at the city's downtown border crossing and shares the images with school principals, who use them as evidence to kick out those living in Mexico. Since he started the...