Brenton Kelly Dickson, 35, is on trial facing multiple charges of persistent sexual exploitation of a child and aggravated counts of indecent assault.
It is alleged he committed the offences against 10 girls between 2007 and 2013.
The court heard he worked at two OSHC programs at primary schools in Adelaide’s north, before being stood down in 2013.
The prosecution has alleged Dickson was overtly physical and playful with the children and some of his offending was “brazen” because he had groomed the children, his co-workers and parents into accepting his behaviour.
In his opening address prosecutor Mark Norman said Dickson was “hiding in plain sight”.
“In the same way we would suggest he was conditioning the children, he was conditioning those he worked with and the parents whose children were involved,” Mr Norman said.
“He was very simply grooming everybody to tolerate what he was doing overtly, on the basis what could be seen was ambiguous and it simply appeared friendly rather than abusive.”
The court heard he was suspended in 2013 after he was seen washing an 11-year-old girl’s legs.
After that incident, the court heard another student complained that Dickson had hugged him, and more children later came forward with allegations of indecent touching.
Mr Norman said a technique the accused allegedly used was “approaching the child who was distressed and taking advantage of that distress to touch them”.
“The accused, according to the complainants, used occasions when they were distressed to approach and abuse them, often isolated in his office or in a nearby room or classroom, which is where the most serious abuse would occur,” Mr Norman previously told the court.