I looked it up. Webster's dictionary has two descriptions that fit our context here:

1. To instruct or educate; to inform the mind; to prepare by instructing in correct principles and habits,

2. To correct; to chastise; to punish.

Clearly, you would prefer 1) to 2).

To see punishing your children as a failure is being hard on yourself.

Is taking TV privileges away for a time an acceptable form of punishment in your view?