I created a Pinterest scraper a while ago which will download all the images from a Pinterest board or a list of boards. It hasn’t been maintained in over a year so use at your own risk (and as of this writing, only supports Python 2.7 but I plan to update it once I get to that part in this lesson.) You’ll also need to install selenium for web scraping and a webdriver for Chrome.
Or you can create your own scrapers: http://automatetheboringstuff.com/chapter11/