## Textbooks

id | Title | Author | Subject | Difficulty_Level | ISBN
--- | --- | --- | --- | --- | ---
1 | Calculus | Isaac Newton | Maths | Intermediate | 9783652003
2 | Physics | Albert Einstein | Physics | Advanced | 9781543220
3 | English Literature | Shakespeare | Literature | Beginner | 9780141029
4 | Biology | Charles Darwin | Science | Intermediate | 9780123456
5 | History | Herodotus | History | Advanced | 9787654321

## Online_Courses

id | Course_Name | Instructor | Topic | Difficulty_Level | URL
--- | --- | --- | --- | --- | ---
1 | Computer Science | John Doe | Programming | Intermediate | https://www.example.com/cs101
2 | Ancient History | Jane Smith | History | Advanced | https://www.example.com/history201
3 | Graphic Design | Mike Johnson | Design | Beginner | https://www.example.com/design101
4 | Quantum Mechanics | Emma Wilson | Physics | Intermediate | https://www.example.com/qm101
5 | Mathematical Logic | William Brown | Maths | Advanced | https://www.example.com/ml101

## Schools

id | Name | Address | City | State
--- | --- | --- | --- | ---
1 | Springfield High School | 123 Main St | Springfield | IL
2 | Evergreen Middle School | 456 Oak Ave | Evergreen | CO
3 | Sunrise Elementary | 789 Pine St | Sunrise | CA
4 | Oakwood College | 123 Maple Dr | Oakwood | TX
5 | Riverview Academy | 456 Cedar Ln | Riverview | FL

## Teachers

id | Name | School_ID | Degree | Years_Experience
--- | --- | --- | --- | ---
|  | (→ Schools.id) |  |
1 | Mr. Thompson | 1 | PhD in Math | 10
2 | Ms. Williams | 2 | MA in English | 5
3 | Dr. Baker | 3 | PhD in Physics | 15
4 | Ms. Rodriguez | 4 | BSc in Biology | 8
5 | Prof. Lee | 5 | PhD in Computer Science | 20

## Students

id | First_Name | Last_Name | Age | Grade_Level
--- | --- | --- | --- | ---
1 | John | Smith | 15 | 9th
2 | Jane | Doe | 16 | 10th
3 | Tom | Hanks | 14 | 8th
4 | Lucy | Grey | 17 | 11th
5 | Michael | Jackson | 16 | 10th