Add high security in schools to prevent unwelcome visitors , keeping school safe

We protect our shops we protect our banks. We even protect residential hotels but we do not protect our children enough. There has been increasing amounts of unwelcome visitors entering schools , Putting lives at risk. There needs to be a level of safety and security for the most precious things that mean the most.
The UK has become increasingly dangerous and a place of education should be at the highest level of safety.