For 2011 and subsequent years, a non-refundable tax credit is available based on eligible expenses paid for the cost of registration or membership of your or your spouse's or common-law partner's child in a prescribed program of artistic, cultural, recreational or developmental activity (eligible program).

The Official CRA site has a full breakdown of the credit and the eligible programs/expenses. Go to  http://www.cra-arc.gc.ca/artscredit/

The CATC will let you claim eligible expenses of up to $500 per year for each of your children who are:

• under 16 years of age at the beginning of the year in which the expenses are paid; or
• under 18 years of age at the beginning of the year in which the expenses are paid if the child is eligible for the disability tax credit.

Also, if at least $100 in eligible expenses has been paid for a child eligible for the disability tax credit, an additional amount of $500 can be claimed for that child.

Beginning with the 2011 personal income tax and benefit return, the Children's Arts amount is claimed on Schedule 1 - Line 370 - Children's Arts Amount

To claim this credit in TurboTax (Interview Steps):

1.  Before you can claim any credits, you will need to enter your dependants. Dependants are entered in the Intro Section of the Interview.
2. Once you have entered your children, proceed through the return until you reach the Deductions section.
3. Click through the screens in the Deductions section until you reach the Claims for Dependants screen. Click YES on this page.
4. On the Dependant Credits screen, click Enter Dependant Credit beside the child you wish to claim the Arts credit for.
5. The Claim Dependant Credits for (Child's Name) screen will appear
6. Check the box beside Children's arts amount.
7. Click Continue
8. On the Children's Arts Amount screen, you can enter the amount of expenses incurred. If you want some of the credit claimed on your spouse's return, enter the percentage on this page as well.
9. Once you have entered the amounts, click Continue. The Arts credit will now be on your tax return

The following is taken from the CRA site http://www.cra-arc.gc.ca/artscredit/. Visit the CRA page for a full list of eligible and ineligible activities and other information on tha CATC.

"To be eligible, a program must be supervised and suitable for children. Eligible programs include:

• a weekly program of a minimum eight consecutive weeks duration in which a minimum of 90% of all the activities are eligible activities;
• a program of a minimum five consecutive days duration in which more than 50% of the daily activities are eligible activities;
• a program of a minimum eight consecutive weeks duration offered to children by a club, association or similar organization offering a variety of different activities when more than 50% of the activities offered are eligible activities or more than 50% of the time scheduled for activities offered to children is for activities that are eligible activities (if both 50% tests are not met, a prorated portion of the fees will be allowed, representing the percentage of eligible activities offered by the organization or the percentage of time scheduled for these activities by the organization); and
• a membership of a minimum eight consecutive weeks duration in an organization if more than 50% of all the activities offered to children by the organization are eligible activities (if the 50% test is not met, a prorated portion of the fees will be allowed, representing the percentage of eligible activities offered to children by the organization).

A program that is part of a school curriculum will be ineligible.

Eligible activities will include an activity that:

• contributes to the development of creative skills or expertise in artistic or cultural activities;
• provides a substantial focus on wilderness and the natural environment;
• helps children develop and use particular intellectual skills;
• includes structured interaction among children where supervisors teach or help children develop interpersonal skills; or
• provides enrichment or tutoring in academic subjects.