Is Lightning Lit enough writing? Or separate writing program?

Just wondering if you’d consider Lightning Lit enough for writing instruction or if we’d want to do a separate writing program.  We haven’t done much writing instruction beyond written narrations, and a few papers here and there for a co-op class.  As we approach high school I feel like we need something a bit more structured and they have both asked for something student-led.  “We don’t want to wait for you – we want to do it on our own,” was the exact quote.  A part of me is all sad that they’re growing up and don’t need me anymore….the other part is all proud of how independent they are becoming!