A Hollister woman was charged Thursday by the Santa Clara County District Attorney's Office with 10 misdemeanor counts for allegedly spiking cups used by pre-schoolers with sleeping pills.

Deborah Gratz, 59, a preschool teacher, was charged with five counts of attempted child endangerment and five counts of assault for allegedly putting the sleep aid Sominex into kids' sippy cups, Deputy District Attorney Sumerlie Davis.

The defendant, who is out of custody on supervised release, is set to be arraigned March 26 in the South County Courthouse in Morgan Hill, Davis said.

Gratz, who had worked at the Kiddie Academy in Morgan Hill since 2007 and supervised nap times of about 10 children aged one and two, Davis said.

On March 8, a fellow teacher noticed Gratz allegedly placed the Sominex into the water cups of the kids and confiscated the containers before they could drink from them, Davis said.

Teachers said they found residue of the sleep drug, which contains a warning not to administer to anyone under 12 years old, in five of the cups, Davis said.

The matter was reported to police on March 11, the Monday after the incident, Morgan Hill police arrested Gratz that day, Davis said.

The district attorney's office cannot prove that any children were actually drugged with anything and filed the charges based on the police report, Davis said.