Mr Vitale is a bit nervous about stepping into the machine about 7pm and is hoping he can fit into his son's wetsuit or "perhaps I'll have to buy one".

Co-organiser Samantha Anstice of the P&F committee says there is a rumour that several former students will be keen to hand over a few dollars to put their former principal in the drink.

Also known as a ducking stool, the device was a feared punishment in the Middle Ages in Europe and later in British colonies in north America. It was part of the wider method of law enforcement through social humiliation.

At the fair it will be good, clean fun, with dunking 'victims' contributing to an expected total of more than $5000.

The fair is the school's main fund-raising event of the year and features a long list of attractions including cyclone ride, chair-o-plane, jumping castle, giant slide, side show alley, face painting, nail and tattoo stickers, showbags, glow products, barbecue, snow cones and fairy floss.

Entertainment comes from the La Dacia School of Dance, Western Port Secondary School drum band, Peninsula Youth Music Society and the Mornington Primary School choir.

Mornington Primary School's Seaside Fair, Pearson

Street entrance, Friday 4.30-8.30pm. Entry and entertainment free. Details: 59752561.