(for the benefit of anyone else in our position. If you are from around Blackheath / Greenwich and going to NW, please feel free to PM me.)
So a bit of digging has revealed the following.
There is a minibus run by Bromley Minicoaches (firstname.lastname@example.org
) that picks up and drops off from Blackheath Standard at 7:30 and 16:30. Price is roughly £5-£6 per day depending on numbers.
) 's minibus from the Greenwich area is not running this year due to numbers. They hope to run it next year. A likely time of 7:10 pickup from Greenwich depending on route has been suggested.
Lots of kids get the 7:53 train from Hither Green. Trains would get back to Hither Green at 16:06 or 16:18. The latter train also stops at Lewisham, from where you can get buses back to Greenwich etc if no-one is available for pickup.
It's a long day, but doable and the commute seems fairly pleasant. I think the minibus option is great while they're finding their feet, maybe migrating to public transport when they get older, or as a backup.