Testimony, which began Monday, resumes Tuesday, and Common Pleas Court Judge Ellen Ceisler said the jury could begin deliberations by week's end.
Prosecutors continued building a case against Shero on Friday, following a turbulent trial session Thursday, when a key witness against Engelhardt and Shero - Edward Avery, a defrocked priest who pleaded guilty to molesting the same altar boy - recanted his testimony.
The three witnesses called by Assistant District Attorneys Mark Cipolletti and Evangelia Manos on Friday testified about Shero's reputation before and after St. Jerome's, when he taught at two other Catholic schools.
"He was always awkward and very touchy-feely, a little too friendly," testified Denise Sosalski. "But he was very standoffish toward me as a mom."
Sosalski said she met Shero about 1996 and 1997, when her son was a pupil at Nazareth Academy in the Northeast. Shero was a teacher assistant at the private Catholic grade school and Sosalski a volunteer.
Sosalski said that Shero then lived a block from her in Academy Gardens and that she once confronted him after her son said Shero invited him and several friends into his house.
"I told him to stay away from my kids," Sosalski testified.
Her son, Roman, now 24, testified that Shero often put a hand on students' backs when helping: "It made me uncomfortable. I just felt it was an older man going beyond what we normally see."
In his questions, defense attorney Burton A. Rose cast Shero in a different light, as an awkward man whose social skills were crippled since birth by severely damaged vision.
Even wearing strong prescription glasses, which distort the appearance of his eyes, Shero in court constantly squints and holds documents very close to read.
Rose asked Denise Sosalski if she knew Shero had been forced to move from her neighborhood because St. Jerome's students pelted his house with rocks.
Sosalski said she did not, but added, "He was really, really odd. I wouldn't be surprised if they lashed out at him."
"So you're saying that if kids think somebody is odd, that's OK?" Rose countered.
"Well, it's one way to get rid of somebody you are afraid of," Sosalski said.
Another witness, Patricia Ann Walton, offered similar recollections of Shero between 2002 and 2008, when he was a resource-room teacher at St. Michael the Archangel parish school in Levittown.
Walton told the jury she volunteered at the church school when her children were there. Although the charge against Shero involves a 10-year-old boy, Walton said she saw Shero mostly around girls.
"It was pretty evident that he didn't like" boys, Walton testified. "He was always yelling at them."
Walton said she complained to the principal and later to local police after witnessing two incidents involving Shero and female pupils.
In the first, Walton said she walked by a classroom and saw Shero and a girl sitting "knee to knee" in two chairs.
"I made a point of letting him know I was there," Walton said, and the girl turned around.
"The young lady was in tears," Walton said, her own voice cracking.
After another incident in which Walton said Shero took pictures of girls on the recess yard, Walton said she contacted police.
The result was a meeting where school officials asked her to confront Shero about her complaints.
Walton said Shero stood up, approached her, and said angrily: " 'See, this is why I get close.' He pointed to his glasses, his blindness."
Contact Joseph A. Slobodzian at 215-854-2985, jslobodzian@phillynews.com, or @joeslobo on Twitter.