Jonathan Isaby, chief executive of the TaxPayers' Alliance, said: "This will certainly raise eyebrows. When authorities are having to find necessary savings taxpayers will wonder if this can be the best use of their money."
The £550 for the archery is part of the commissioner's youth diversion fund, which aims to educate young people and divert them away from crime and anti-social behaviour.
Around £61 million of cuts have been made to Kent Police since 2010 and up to 1,220 job cuts have been made across the force.
Mr Isaby added: "Innovative ways of keeping kids out of trouble can be a good thing but costs must be kept down. Residents will want to keep a close eye on the scheme to see if it really does yield results."