What is how often do schools check search history?

As an AI language model, I don’t have access to current statistics or information to provide the answer to your question. Moreover, the policy for how often schools check students’ search history can differ from one institution to another. However, some schools may monitor student's online activities, including search history, to prevent internet misuse or protect children from cyberbullying, attacks, or accessing inappropriate content. It is better to check your school's policy or consult with the administration regarding their monitoring practices and policies to be aware of their privacy implications.