By Charlotte Beugge

A fifth of students aged 16 to 18 have store cards - but 71% of this age group doesn't know what an APR is, according to research from the Chartered Insurance Institute (CII). 17% of these teenagers took out the store cards themselves.

Store cards can charge rates of interest of up to 30% as will be shown by the APR, which stands for annual percentage rate. Not understanding how much interest will be accrued if bills are not paid off in full could be expensive for young people.

But this was not the only worrying gap in the students' knowledge, as 73% did not know what "equity" meant, the meaning of "credit" defeated 33% and 24% didn't know what "debit" means - even though 95% had a debit card.

The CII says that 39% of the students it surveyed had not received any kind of financial education at school. Nearly half (45%) of secondary school teachers surveyed said there was too little time and not enough resources to teach the subject.

Most of the students surveyed were nonchalant about debt, with 51% saying it is "something everyone goes through at some point". Nearly a third (32%) said credit was "useful", with 12% saying it is "hard to come by".

David Thomson of the CII commented: "It's crucial for this age group to have a good understanding of personal finance as many of them will set off for university and have to budget for themselves for the first time."