District spokeswoman Diane Boyett says it appears the death was possibly caused by a choking accident.
Boyett says Hernandes was assembling ingredients to prepare s'mores as a writing activity with a camping theme. The campfire dessert uses marshmallows, chocolate and graham crackers.
The Victoria Advocate reports a teacher saw the boy collapse after he said he did not feel well and needed water.
A school nurse and Victoria fire department employees attempted to resuscitate Hernandes, who was pronounced dead at a hospital.
