Buses and trains have priority seats for old people, pregnant people, and people who need them for other reasons. I say expand that to be a whole section instead of some seats, and add a mandatory age limit to that section where you have to be over either 15 or 18.
#PublicTransportation
@macberg what if you're 16 and pregnant and disabled?

Surely just a sign saying Fuck Off Kids would suffice.
@inpc There can be some priority seats in the kids section as well.
@macberg what if its a family with two children, 1 is disabled, a pregnant mother, with her 15 year old sister and the granddad, who just happens to look like Ossie Osbourne and doesn't like sparrows.

Have you thought this through?
@inpc Easy. There'll be a trailer for cattle behind the bus, the trailer has a couple of seats and sparrows are only allowed on there if they have purchased a season ticket, in which case the family have to either wait for the next bus or challenge the sparrow(s) to a duel.