If you have expenses that are eligible for both childcare expenses and fitness/art costs, you should claim childcare expenses first, it is allowable by CRA and it is better for you because childcare expenses takes direct deduction so they reduce you taxes by your marginal tax rate. Fitness costs, however, only takes a 15% credit rate (in Ontario, if total costs is less than $560 (for 2016 tax year), you have additional 10%, still lower than your marginal tax rate).
If you can't claim all the expenses as childcare expenses, you can claim the rest as fitness/art amount.