I've worked in both settings. I tend to follow a child-centered approach either way, but how I do that is very different depending on a setting. In a classroom, you're going to need a very clear lesson plan because otherwise everyone will be running everywhere. If one or two kids in a larger class isn't feeling an activity on a particular day, I will redirect them as appropriate, but continue on with the activity for everyone else. When I nanny, I always have a game plan in mind for the day, but I feel like when you're only watching maybe 1-3 kids, you need to take their moods and desires into consideration. So my plans when I nanny are not nearly as detailed as when I have taught to allow that flexibility.

Its rare to find a nanny job with a 3 year old or older child that isn't in preschool. If you will be happier in a job where you use your degree, develop lesson plans, come up with themes and activity planning for educational goals then you'll be happier in a daycare or preschool job than a nanny job.