Help them how, exactly? What else can you do but leave them alone to figure it out? All you can really do is remind them to sit down with the coach at the end of the season to talk about their role, progress, and future with the team.
I think what you mean is that you want lots of examples like the one you cited, about players who didn't play well as freshmen and then did better in subsequent years. Unless you know what it was that turned them around, using them as examples may not mean much. Plus, it will vary from level to level and from team to team.
Even if you have those examples, every kid is going to have a different take on what he wants to put into baseball, what he hopes to achieve, and whether it's worth continuing.