No, I didn't keep a journal till much later. When I was in grade school, no one told me how valuable a journal is. Maybe I should say I don't remember anyone telling me. I wasn't always listening.
Journals have unique power.
Sometimes that does seem to be true, but it's really only a half truth. Here's an example. I have pictures of friends from school years and later, but now I can't even remember some of their names, let alone some of the things we did together. That's because pictures have only one dimension. All you have is what you see.