* Public Schools (K-12): The Irvine Unified School District (IUSD) encompasses numerous elementary, middle, and high schools. The exact number fluctuates slightly as schools are sometimes reorganized or built, but it's in the range of 30-40 schools within the IUSD.
* Private Schools: Irvine also has a number of private schools, including various religious and secular options, at all grade levels (preschool, elementary, middle, high). The number of private schools is much smaller but is at least in the tens.
* Colleges and Universities: The University of California, Irvine (UCI) is a major university in Irvine. There might also be smaller colleges or vocational schools. Including UCI, it's a minimum of one, but possibly more.
Therefore, a precise number is impossible without a very specific definition of "school" and a very up-to-date count of all institutions. A reasonable estimate would be somewhere between 40 and 50, but this is only an approximation encompassing public and private K-12 schools, and including UCI.