"I observed girls trying to get away from him," Corder added. "Some were able to get away. Others were not.”
Hopkins, a graduate of Springboro schools and son of a longtime Springboro teacher, also coached swimming at Coffman Y in Springboro, prior to the case.
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He was placed on leave in last March, two days after a parent talked with their daughter about sitting on Hopkins' lap.
On the witness stand, the father testified it was “almost frightening as a parent to hear your daughter say what happened.”
"My daughter was very excited about it,” he added about what he described as "a parent's worst nightmare".
Later, the girl, 8, testified she never talked about it with her father.
Prosecutors need to prove Hopkins was sexually gratified by interactions with the children, pulled from close to 300 hours of surveillance video of Hopkins' classes.
Carrie Hester, now the district superintendent, testified about four video fragments she saw Hopkins with an erection.
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“You see much more of a bulge,” said Hester, at the time the human resources director.
The defense presented video and asked Hester questions about whether it could have been his cellphone.
Hester and Corder said Hopkins panicked as he was put on leave and made incriminating statements.
There was also testimony about a door bell Hopkins installed on the classroom door, without permission.
Other teachers installed door bells to help in situations where doors are to be locked for security, Hester said.
Hopkins' lawyers showed video showing other school staff in similar positions with students and segments of students greeting him with hugs as he entered the classroom.
There were disagreement about whether Hopkins was properly trained to teach first graders.
Before the trial began Tuesday, the school district's lawyer raised the issue of revealing personally identifiable information abut past or current students.
“If someone refuses to answer a question, I’ll order them to answer,” Judge Robert Peeler said.
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