Glean (https://www.glean.com/) is a learning platform designed to enhance student engagement and knowledge retention through active learning techniques. It provides a range of features that aim to improve the learning experience for both educators and students. While my knowledge is based on information available up until September 2021, I can provide an overview of Glean's features and suggest some alternative platforms that offer similar functionalities.

Key Features of Glean:

1. Note-taking and Highlighting: Glean offers a note-taking feature that allows students to capture key points during lectures or while studying. It also enables highlighting of important passages in digital textbooks or other learning materials.

2. Interactive Quizzing: The platform includes interactive quizzes to help students assess their understanding of the material. These quizzes can be used for self-assessment or as part of formal assessments.

3. Collaborative Learning: Glean promotes collaboration among students through its interactive platform. It allows students to share notes, discuss concepts, and engage in group activities, fostering a collaborative learning environment.

4. Analytics and Insights: Glean provides analytics and insights to both students and educators, allowing them to track progress, identify areas of improvement, and gain a deeper understanding of student engagement and learning patterns.

5. Integration with Learning Management Systems (LMS): Glean integrates seamlessly with popular learning management systems, making it easy for educators to incorporate it into their existing teaching workflows.

Alternative Platforms:

1. Notion (https://www.notion.so/): Notion is a versatile platform that allows users to create and organize notes, collaborate on projects, and build databases. While it offers a broader range of features beyond learning-specific functionalities, it can serve as a flexible alternative for note-taking and collaborative learning.

2. Perusall (https://perusall.com/): Perusall is a social learning platform that promotes active reading and collaborative annotation. It enables students to annotate texts, ask questions, and engage in discussions within the reading materials. It emphasizes peer learning and includes analytics to monitor student participation and comprehension.

3. Kami (https://www.kamiapp.com/): Kami is a digital tool that focuses on document annotation and collaboration. It allows students to mark up PDFs, add comments, highlight text, and work together in real-time. While its primary focus is document annotation, it can be useful for active learning and collaborative studying.

4. Quizlet (https://quizlet.com/): Quizlet is a popular learning platform that offers flashcards, quizzes, and study games to aid in content review and memorization. It provides a vast collection of user-generated study materials across various subjects, making it a useful resource for students seeking additional practice and reinforcement.

It's worth noting that the landscape of educational technology is continually evolving, and new platforms with similar or enhanced features may emerge. Therefore, it is recommended to conduct thorough research and explore the latest options available to find the platform that best aligns with your specific learning needs.