never really thought about attending ground school as it's more school!
Well, it's simple. You've got a new skill to learn. You can either learn that skill on your own (using books, DVDs, whatever) or get some sort of guided learning where an actual instructor will tell you what you need to know.
It's up to you to decide what works best for you. Despite being a professional teacher (IT though, not aviation), I'm the type that fancies self-study over classroom. But not everyone has the discipline for that. (And frankly, if the subject doesn't interest me all that much I lack the discipline too.) In which case a classroom course is probably easier.
One word of warning though. If you do decide on getting groundschool, don't approach it as if it's "more school". I have taught at highschools, and I'm now teaching commercial IT courses and the major difference is student motivation. Typical adolescents will attend school "because they have to" and the teachers waste a lot of time getting through to an unmotivated class. In contrast, adults are very, very motivated in class. They made the choice themselves and in case of PPL groundschool, they pay for it themselves. You will typically find that they're staying late to ask yet more questions, will not let go of the subject during breaks, and they will certainly not appreciate others showing unmotivated and disruptive behaviour.
I have occasionally had students in my commercial classes that were fresh from highschool and still showed the behaviour that they exhibited there. In most cases peer pressure alone was enough to change that in a few hours, and otherwise they got a nice little lecture from me during the first lunch break.