Quarterlies are distributed through local churches. They are not free, however most churches cover the cost of them for their own members. If you are unable to acquire a copy through your church, you can purchase them at the Adventist Book Center or use the Sabbath School Net web site at http://ssnet.org/ and click Study Guides. From there, you can study via the web site, download PDF versions, or find the link to the free iPhone/iPad/Android Sabbath School app.