TODDLERS may be admitted free and student rates extended at Urban Council swimming pools to encourage youngsters to splash out and exercise. The council's standing committee will review the proposal early next year. A working group expects little revenue loss and proposes the changes be implemented in time for next year's swimming season. A spokesman said it would give a greater incentive to students to learn and practise swimming. 'We believe the loss in revenue . . . will be off-set by an expected higher attendance at swimming pools coupled with the additional advantage of an improvement of the swimming ability and physical fitness of students.' He said the council conducted a study in July which revealed toddlers only accounted for 1.1 per cent of total admissions to its pools. Waiving their admission fee would lose only an estimated $35,000 a year. Pool admission fees for adults are $17. The concession for senior citizens, the disabled and children under 14 is $8.