Wiktionary
study circle
n. A club or informal group of people sharing knowledge of a specific subject.
Wikipedia
Study circle
A study circle is a small group of people who meet multiple times to discuss an issue. Study circles may be formed to discuss anything from politics to religion to hobbies. They are differentiated from clubs by their focus on exploring an issue or topic rather than on activities or socializing. When they emerged in the early twentieth century they were based on a democratic approach to self-education and were often linked to social movements concerned with temperance or working class emancipation.