Admission to the Grandes Écoles is very different from that of French universities. Except for certain special academic programs, French universities were required by law to admit in the first year of undergraduate studies any student having completed the national baccalauréat, regardless of students' other grades or qualifications. This was in contrast with the selective admissions system for French Grandes Écoles, as explained below.
To be admitted into most of the French Grandes Écoles, most students study in a two-year preparatory program in one of the CPGE (see below) before taking a set of competitive national exams. Different exams are required by groups (called "banques") of different schools. The national exams are sets of written tests, given over the course of several weeks, that challenge the student on the intensive studies of the previous two years. During the summer, those students who succeed in the written exams then take a further set of exams, usually one-hour oral exams, during which they are given a problem to solve. After 20 minutes of preparation, the candidate presents the solution to a professor, who challenges the candidate on the answer and the assumptions being made. Afterwards, candidates receive a final national ranking which determines admission to their Grandes Écoles of choice.
Preparatory classes to the Grandes Écoles (CPGE)
Classes préparatoires aux Grandes Écoles (CPGE) or prépas (preparatory classes for the Grandes Écoles) are two-year classes, in either sciences, literature or economics. These are the traditional way in which most students prepare to pass the competitive recruitment examination of the main Grandes Écoles. Most are held in state lycées (high schools); a few are private. Admission is competitive and based on the students' lycée grades. The preparatory classes with highest success rates in the entrance examinations of the top Grandes Écoles are highly selective. Students who are not admitted to a Grande École of their choice often repeat the second year of preparatory classes and attempt the exam again the following year.
There are five categories of prépas:
Scientifiques: These prepare for the engineering schools and teach mathematics, physics, chemistry, and technology. They are broken down in sub-categories according to the emphasis of their dominant subject: they are mainly focused on mathematics and either physics (MP), industrial sciences and technologies (TSI), physics and chemistry (PC), physics and engineering science (PSI), physics and technology (PT) and chemistry, physics and technology (TPC) .
BCPST: biology, chemistry, physics, geology, and mathematics. Commonly called "Agro-Véto", these classes prepare students primarily for agricultural and veterinary schools, but also for schools in geology, hydrology, and forestry, as well as for research and teaching careers via the Écoles normales supérieures.
Lettres: humanities, essentially for the Écoles normales supérieures (students can also compete to enter business schools, but represent a small minority of those admitted). There are two main sub-categories: "Lettres", in either "A/L" (with Ancient Greek and/or Latin) or LSH (with geography), and B/L (with mathematics and social sciences).
Économique et commerciale: mathematics and economics. These prepare for the entrance exams to the French business schools, and are subdivided between science (mathematics) and economics tracks - a third track also exists for students with a "technological", i.e. applied background.
Chartes: humanities, with an emphasis on philology, history and languages, named after the school École Nationale des Chartes. By far the smallest prépa in number of students.
Recruitment at baccalauréat level
Some schools are accessible after a selection based on the grades of the two last years of lycée and/or the baccalaureate results. For example, in engineering, there are the six schools of the INSA network, the three Universités de Technologie, the three schools of the ISEN group, and the thirteen schools of Polytech Group. It is also possible to join these schools in third year after a preparatory class or university and then the recruitment is based on a contest or the student results.
The top five of these engineering Grandes Écoles according to the French magazine l'Usine nouvelle are in 2014: UTC, INSA Lyon, ESTACA, UTT and EPITA.
Most of them simply include the two-year preparatory class in their program while others like INSA Toulouse chose the LMD to start the specialization earlier. Most students choose to get their licence, master or doctorate close to home.
These years of preparation can be highly focused on the school program so students have a greater chance of succeeding in the admission exam or contest in their school if there is one, but they are not prepared to take the examinations for other schools so their chance of success in these other examinations is low.
The advantage is that instead of studying simply to pass the admission exams, the student will study topics more targeted to their training and future specialization. The main advantage is that students choose their speciality more according to their interests and less according to their rank. (Indeed, the rank obtained after standard preparatory classes determines a list of schools with their specialities).
The selection process during the first preparatory year is considered less stressful than in a standard first preparatory class. Nevertheless, the selection percentage can be the same as during standard preparatory classes. These schools also recruit people who did not manage to follow the programs of CPGE.
Parallel admission
In many schools, there is also the possibility of "parallel admission" to Grandes Écoles. Parallel admissions are open to university students or students from other schools. The prépas years are not required to sit the entrance exams, provided that the candidates performed well in their previous studies. This method of recruitment is proving increasingly popular, with many students choosing to go first to university and then enrol in a Grande École.
Some Grandes Écoles have dual diploma arrangement in which a student can switch establishments in the last year to receive diplomas from both establishments.