At what age should your child/children start having pocket money?

I started having poket money from the age of 10 because i was in boarding school ,
normally, it was a fairly huge amount and i squandered it all on ;Dcowbell milk but i gradually learnt how to 'economise' and saved as well, maybe 10 is the right age,

my children have had bank accounts since they were born. I made them aware of the accounts at around 5. and they manage thier own accounts.

They save or spend as they want and get reward from us for saving more than they spend.

It goes like this:

who ever has the most money at the end of each month earns 10% interest on thier account
Who ever has the least amount debited from thier account each month earns 50.00

Now the most they ask for is about 10-15 per month to walk around with.
They save thier allowance and view thier accounts online.

if they live in school i think it should when move in but if living with parents I'd say maybe around stating from 13 or 12

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