Giovanni Peña, 31, was the victim's teacher last year. He sexually abused the child by touching the boy's clothed penis and buttocks, prosecutors said. Peña also sent nude photos of himself to the child using Snapchat.
Peña was arrested in June. He pleaded guilty Friday to one count of second-degree child sexual abuse and one count of obscenity.
Peña will remain in jail until he is sentenced September 4.
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