[juancb]

Sounds like it's time for them to get their own bike to ride to school?

You can ride with them on a few practice runs on a weekend and then continue to do so on a weekdays. Once you're both comfortable with the route and their ability to navigate it safely you can cut back on how much of the route you do together or just let them run it on their own. That last bit is a call to be made based on a lot of factors including your kids desire to ride with you.