First, we painted both the pots and the saucers white. We had to do three coats of white to get the terra-cotta color really covered over, and we may have gotten some paint in our hair… but acrylic paint dries pretty fast so it was no big deal.
The sponges covered over all manor of paint sins. I got these neat little sponge-on-a-stick paint brush things at the dollar store that we used to make the white dots on top the toadstools.
I used a sharpie to draw a door shape on the pots once the white paint was dry, and let the kids paint them in.