Here is the list of top science colleges in Tamil Nadu offering courses like B.Sc , M.Sc, M.Phil/ Ph.D in Science , B.F.Sc. and M.F.Sc :

1. Loyola College

2. Madras Christian College

3. Cheran Arts and Science College

4. Stella Maris College

5. Cheran College for women

6. Presidency College

7. S.M.S College of Arts and Science

8. Ethiraj College for Women

9. Kumaraguru College of Liberal Arts and Science

10. Ramakrishna Mission Vivekananda College

The pattern of fee structure and entrance examinations generally vary from university to university. So I would suggest you to have a look at the official website of the college for the information on fees and entrance examination of the particular course you want to know for.

Hope it helps.

Good Luck!