The number of children under 16 years old opening second level accounts has quadrupled over the last five years, according to Bank of Ireland, which recently introduced its school banking package.

"In 1997, the under-16 age group accounted for only 10 per cent of the second-level accounts opened.

Today, that figure is almost 40 per cent. Students are starting to bank at a much younger age," says Mr Patrick Farrell, marketing manager for customer recruitment at Bank of Ireland.

Part-time jobs have been the main driver for the number of accounts being opened by 15- to 18-year-olds, Mr Farrell adds, because employers often pay electronically and because teenagers have more cash to keep safe.

"We've seen a lot of accounts at secondary school level opening during the summer months, when 15- to 18-year-olds might get jobs at their local Spar, Centra or wherever," he says.

"Teenagers today have access to increasingly larger amounts of money," says Mr Farrell. The average annual turnover on accounts among 15- to 18-year-olds is approximately €1,960, according to Bank of Ireland data.

Among 12- to 15-year-olds, the annual average is €358.

"School students have no expenses. In fact, a school student who works at the weekend has almost as much disposable income as an older person who is working, when you take mortgage repayments and everything else into account," he says.

"People can see this is a consumer group with big clout."

Under the bank's current account for second-level students, credit balances accrue interest of 2 per cent to 2.5 per cent per annum.

Second-level students are also opening accounts in order to use ATMs to top-up mobile phones. According to Mr Farrell, parents will still pay for things like mobile top-up cards for children in the junior cycle of second level, but once they hit the senior cycle, teenagers will pay for cards themselves.

"Definitely, mobile phones are one of the main expenses. After that it's clothes and CDs."