Isobel Thomas, a Glasgow parent, has complained that her son Jason, aged 16, a pupil at Williamwood High in East Renfrewshire, has had his application rejected.
Mrs Thomas says East Renfrewshire refuses to pay Jason pound;19.77 a week because he does not live in the authority, while Glasgow turned down her application because he does not attend one of its schools.
Mrs Thomas has now enlisted help from Brian Monteith, the Tories' education spokesman, who commented: "The authority where the parents stay is the authority that should pay because that is where they make their council tax contribution."
A resolution could be at hand in the form of educational maintenance allowances, which are being piloted in East Ayrshire from next week.
Participants have to sign up to learning agreements linked to exam performance, attendance and behaviour. The maximum grant is pound;40 a week if family income is below pound;13,000, reducing in stages up to a ceiling of pound;30,000.
It is paid by the authority in which the student lives irrespective of where they study.