Primary schools have criticised South Holland District Council after it doubled school swimming fees on the same day it made sessions for under-16s in their leisure time free.
The 50p charge introduced last April for the 1,000-plus pupils who use the Castle Pool in Spalding was increased to £1 on April 1.
Schools say the price hike is harsh on pupils in rural areas, whose parents already have to stump up travel costs to the pool and who are less likely to be able to take advantage of the free swimming offer because of poor transport links.
Moulton Chapel Primary School headteacher Geoff Palmer said: "It is a form of rural deprivation.
"If a family has only got one car and the dad's got to get out to work then you can offer as much free swimming as you like but our pupils won't be able to get there. With school swimming they are taken there.
"I know that the council have got to raise revenue but this is an easy target."
Fewer children at the school have swimming lessons following last year's charge and later this month the school will discuss how much of this increase it can pay and how much will be met by parents.
Gosberton Clough and Risegate Primary School headteacher Alan Hughes said: "It seems a little bit unfair and unbalanced that other children can swim for free but small primary schools pay over the top."
District council deputy leader and leisure portfolio Nick Worth said free leisure time swimming sessions are part of a separate, Government-funded scheme.
He said the extra revenue from the increase will be passed on to pool managers Leisure Connection, saving the council £20,000 in management fees.
Coun Worth, chair of governors at Holbeach St Marks and Gedney Drove End primary schools, said: "Schools have got a budget from the county council for education which includes swimming."
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