For the last two years, Derrick Lacasse has been the grade K-8 music, band and chorus teacher at Saint Dominic Academy.

The busy 23-year-old is also assistant tennis coach and drama co-advisor in addition to teaching voice lessons at Community Little Theatre’s summer theater camp.

“The ‘aha!’ moment, I love seeing that,” said Lacasse, who grew up in Auburn and now lives in Lewiston. “All the hard work they’ve put in and I’ve put in, (when) it’s finally becoming a result, it’s finally something you can see on their faces.

“Why I like working with kids is that sort of joy is so innate,” he said. “When you’re working with teens, it’s harder to get at it. ‘I don’t want to look bad in front of my friends, I don’t want to look stupid.’ Working with kids, they don’t have that sort of fear.”

Lacasse, who has been singing, playing musical instruments and acting since middle school, has worked with CLT since a production of “Annie Get Your Gun” 10 years ago. He was the dentist and three different reporters during last month’s “Little Shop of Horrors.”

This fall, he’s moving from teacher to student: Lacasse is headed off to graduate school in Massachusetts to study music therapy, something he was introduced to while earning his bachelor’s degree.

“We had students with autism and physical disabilities,” Lacasse said. “I saw that music in that sense was such a strong influence — they really wanted to make music. Like, if a physically impaired student can’t reach an arm out, they’re more apt to reach an arm out to play a drum or hit cymbals. Just the fact that music can be used as a tool to help people in need is amazing to me.”

kskelton@sunjournal.com