They held a vigil for 14-year old Amy Nguyen and her 4-month old sister at Woodcrest Junior High.
Last week, the girls' father returned home to find them dead in the garage and his wife, Linda, unresponsive.
Amy was a special needs student.
One of her classroom aides is among the many shaken by her death.
"She always used to say hi to me," said Sergio, a class aide for Amy. "It really made my day when she said hi to me."
Linda Nguyen has been charged with murder.
She's being held without bail.