Do nonprofit organizations need permission to photograph their members for promotional use?

[Vanessa]

We are starting a small non-profit childcare organization in our city. We will be creating promotional materials such online (website, social media) and printed media (brochures, flyers, pamphlets etc.). Do we need a "Permission to Photograph" form if we wish to photograph our members during meetings, events and workshops if we will be using these photos on our promotional materials?
I'd like to clarify. The nonprofit organization will be a childcare association. Our services will be catered towards childcare providers.