Martin Lewis warned that children struggle to recognise the difference between real money and money spent on applications on mobile devices and tablets.
The financial expert told MPs at the Commons Education Committee on Tuesday (5 March) he hears from parents whose children have spent money on purchases inside games.
"In the old days when you had cash and you had money in a game, the money in the game wasn't real and the cash was real. Now the two things are very similar," Mr Lewis said.
During the same committee hearing, schools minister Damian Hinds pulled faces behind Mr Lewis as he criticised the government's "political failing" in financial education.
