The tuition credit is a non-refundable tax credit. So if your tax payable is already at Zero, you don’t get any of the credit. However, it will be carried forward to future years, until it is used up.
For tuition amounts on your current tax year (2017) T2202A, you can transfer up to $5,000 of your tuition to a spouse, parent or grandparent if they have taxes payable.
More useful information for Students: https://turbotax.community.intuit.ca/replies/2648040