It would help that they had someone their age they could cycle with from time to time. Is there an annual fundraising cycling ride for whomever is interested, to "train" towards as a fun goal?

And probably if they had a local parent/aunt or sibling who cycled also. Even the brightest, most motivated girl needs and wants social support at that age, for a solo-oriented sport like cycling.

Suggest the girls might journal their cycling so that they can make observations (anything) and track some mileage if they wished. Or offer a modest prize..for a collective team effort or picnic in late spring to celebrate. A social event to celebrate cycling effort.

ANd great newsmith that you're doing something!