When setting up a system, you should make only the first user account an Administrator account, even on a child’s machine. Be sure to choose a good password to protect the Administrator account. By default, this first account had approval mode enabled, meaning it can be used to configure Parental Controls and manage any setting on the system. All subsequent user accounts you create —especially for kids—should be setup as Standard Users. If a user with a Standard User account needs to complete a restricted task, installing a program for example, the Administrator can enter the proper credentials to complete the task.
For normal system use you should be able to login as a Standard User, and enter your Administrator credentials only when a task requires it. Taking this extra step when you need it will help prevent accidentally doing something you didn’t mean to do – or installing something you know you shouldn’t.