Things you con control are consistency and communication. We use mostly email listervs and some social media posts as reminders. We always meet in the same place, same, same day of the week, every time school is in. We try to make things fun with music, holiday lights, stickers, hot cocoa, etc.
Out of your immediate control is actually having a feasible, safe route to ride. The lack of safe routes can lead parents to local advocacy.
What else am I missing? Anything you can add?