I have actually managed to get it together and book a venue and time for trying out a parents-and-kids choir. The idea is basically that parents turn up, bring their kids, and we all sing in the same room while the kids play (hopefully not super loud).
I've booked the Harry Miller Hall at the Greyfriars Charteris centre (the old Kirk O'Field building on the Pleasance) from 2-4 on Sunday 3rd July and Sunday 17th July, to try out a couple of "taster sessions" - if these go well then we'll hopefully start it properly in September.
Hiring the hall does cost £50 for a 2-hour session, so I'll have to ask for a small financial contribution - would £5 per adult and £2 per child be acceptable? If that cost is a barrier to you, let me know and we can work something out.
If interested, please email me at firstname.lastname@example.org and let me know how many adults and children you'd like to bring (max 2 children per adult please, if you want to bring more children please supply an extra adult).
For more details, see public entry on Facebook: https://www.facebook.com/hutchingsm