Our comprehensive work questions secondary teachers’ statements on their ICT usages, in particular Internet, as well as what they believe students do with it. The goal is to better understand the use of Internet in education. We discover that among the 2 862 teachers we interviewed, variables (discipline, gender, age…) influence their use of digital tools and the place they give them in their professional practices. Our investigation reveals contrasting positions, divisions of opinion that reflect a lack of epistemological maturity today. The results also draw the outlines of the evolution of teachers’ mentalities that augur a promising future is possible for the use of Internet in education and training while today it is still insufficiently reasoned.