The programme helps older people to be active, to connect with others, learn something new, take notice of their own and other people's feelings and give their support to the local hospital.
This class full of golden oldies ticks all of the boxes in the Mental Health Foundation's Five Ways to Wellbeing.
There's a lot of laughter as the women do a series of other exercises aimed at coordination, flexibility and strength - all catered around those who not always able to exercise standing up.
It's a class that provides much more than a chance to stretch and flex.
"Music can shift anyone's mood," says Lorraine.
"We sing and dance along and in this age group it doesn't matter if we make a faux pas. No one's judging you."
As well as the feel good factor Phyllis has experienced the physical benefits of exercising. A while back Phyllis says, she couldn't reach up to lock her ranch sliders at night - a hazard for someone living alone. Now she can.
Lorraine flexes her fingers. A few years ago she was in a serious car accident and has a steel plate in her hand. She couldn't move a finger. Now she demonstrates how well her fingers can move.
Shirley herself, who's been doing ballet since the age of two, is living proof that exercise keeps you fit, active and able to continue contributing something meaningful to the community.
It's obvious that Shirley loves what she does. The routines are carefully choreographed with specially chosen music and she keeps things lively with the use of props like the coloured plates and plastic balls. She cares about her students, phoning them if they've been away or sending cards.
"The greatest pleasure for me is to see people come back to class and say they have missed the social contact. Twice a year we go out for luncheon, and during the year we have raffles with proceeds going towards wool for the ladies to knit for the prem babies at Waitakere Hospital. What money not used for wool, we choose a local charity to give it to."
Indeed, about three times a year banana boxes full of blankets, booties, tiny singlets, slippers and teddy bears are dispatched to the hospital. The group also runs a book exchange and sometimes there are plants and produce too.
"Everybody's doing a little something out there for others," Shirley says.