The adoring teacher looked down and returned their smiles, while pointing at her own tongue, stuck to the roof of her mouth.
William, Genna, Sarah and Isla sat enraptured, little bums on floor cushions, big eyes gazing up at Kathy Campbell.
''Can you all say 'Nnnnnnnn?''' she asked. ''Nnnn was our tricky letter this term, wasn't it? Nnnn is for nest. Today we're going to make a nnnest.''
So began another Monday morning class at Begin Bright in Balwyn North, the latest extracurricular option for education-conscious parents of kids as young as two.
This is tutoring for tots - or prepping for prep - in which preschool-age children learn everything from basic literacy and numeracy to how to hold a pencil.
In the tutoring industry, ''school readiness'' programs such as these are emerging fast, spurred by parental anxiety and a competitive education system.
Begin Bright - a leader in the field - has 10 locations in Queensland and New South Wales. Balwyn North is the first in Victoria, and the 11th franchise overall.
Kathy Campbell opened the centre 10 weeks ago, after teaching prep and grade one for five years. She has already signed 15 students, with more joining every week.
The lessons she offers are more formalised and structured than those at pre-school, kindergarten or day-care - but the children are hardly chained to desks, either.
Before making colourful nests out of cupcake holders and shredded paper, they sat in a circle and read a book featuring Numbat Nat (or ''Nnnnumbat Nnnnat'').
They learned the basic shape of the letter N with flashcards. Then they practised writing ''n'' on a whiteboard, as well as a decorative worksheet.
These Monday morning kids form ''the green group'' - a one-hour class for children aged three and four who plan on going to school in 2016.
''We want to alleviate the stress they may feel about going to primary school,'' Ms Campbell said. ''Our main focus is to make them feel smart, happy and confident.''
Katrina Naish of Greensborough has been bringing her son William, 3½, since the start of term, after remembering her own struggles with English.
''For me it's about keeping up,'' she said. ''For my husband it's about getting ahead.''
Catering to those exact needs, Kumon, the largest tutoring company in Australia, has seen massive growth in pre-school tutoring enrolments.
And the market shift for Kumon has been pronounced in Victoria where, in 2013, 23 per cent of their English students and 11 per cent of their maths students were pre-schoolers.
Professor Joseph Sparling, an early childhood expert at the University of Melbourne, said he was wary of structured tutoring at the expense of play-based learning.
''The value of these early academically oriented programs is really anybody's bet,'' he said. ''I'm rather sceptical myself.''
Ms Campbell, however, said she was confident the program did not push children too hard - that it made them feel happy in a structured learning environment.
On the question of helpful or harmful, Emma Bello is a true believer, having seen results since first bringing her daughter Isla, 4, to Begin Bright seven weeks ago.
''I think it's great,'' Ms Bello said. ''Her letter recognition is amazing. She'll be sitting in the car and go, 'Traffic light starts with T!' She's just skyrocketed.''