Class 7 Social Science (SST) covers various subjects such as History, Geography, and Civics. To enhance your understanding of these subjects, there are several reference books recommended. Here are some popular options:

1. NCERT Social Science Textbooks:
- These are the official textbooks prescribed by the NCERT (National Council of Educational Research and Training) for Class 7 SST.
- They provide comprehensive coverage of the topics and concepts in a structured manner.
- The language used is easy to understand, making it suitable for students.

2. "Our Pasts II" by NCERT:
- This book specifically focuses on History and is a part of the NCERT textbook series.
- It covers various topics such as the Mauryan Empire, Mughal Empire, and the growth of towns during medieval times.
- The book includes engaging narratives, illustrations, and maps to make learning more enjoyable.

3. "The Earth: Our Habitat" by NCERT:
- This book is a part of the NCERT textbook series and is dedicated to Geography.
- It covers topics like the Earth's structure, climate, natural vegetation, and resources.
- The book includes colorful diagrams, maps, and real-life examples to enhance understanding.

4. "Social and Political Life II" by NCERT:
- This book is a part of the NCERT textbook series and focuses on Civics.
- It covers topics such as the Indian Constitution, the judiciary, and the role of the government.
- The book includes case studies, activities, and thought-provoking questions to develop critical thinking skills.

5. "Golden Social Science: A Book with a Difference":
- This reference book is published by New Saraswati House and is designed to supplement the NCERT textbooks.
- It provides additional exercises, practice questions, and explanations to reinforce learning.
- The book also includes attractive illustrations and examples to make studying more engaging.

Remember, while reference books can be helpful, it is important to prioritize the NCERT textbooks as they are specifically designed to align with the school curriculum. These reference books can be used as supplementary study material to gain a deeper understanding of the subject matter.