Student with a degree in Biology offers private lessons and homework help to strengthen anyone wishing to improve in the scientific fields: Science of Life and Earth (Biology + Geology), Mathematics, Physics and Chemistry. My method is this: to review the theoretical bases of the lesson, the lesson, or a problematic exercise, and so on. Then, once the theory is understood, we move on to practice with the exercises. And as it is by forging that one becomes a blacksmith, I propose a variety of exercises allowing, eventually, to master the subject.