If you read the British press recently, you saw regular front-page stories about "Islamic Trojan Horse" schools. Apparently, some muslim radicals hatched a plan to put their people onto school boards and then to use those people and/or parent pressure to make life so difficult for principals that they resign.
The principal vacancies can then be filled by the hijacked board with sympathetic souls who will introduce desired changes or hire desirable faculty. Such changes might include boy/girl segregation, certain styles of dress such as scarves for girls, the inclusion or removal of specific curricular content and so on. The goal would be to produce what are in effect state-funded and state-provided madrasas.
These claims caused something of a furore in the UK. Government inspectors were dispatched to visit some of these schools, and reportedly the inspectors found that such events and personnel and curriculum changes did occur. As a result, some school-boards were dissolved, people lost their positions and statutory managers were imposed. Some academies (charter-schools) had their licenses taken from original sponsors and handed over to other sponsoring groups.
What I find interesting about this is that no-one mentioned the similar efforts of evangelical christians. When I was a student teacher, I noticed the majority of my peers were evangelical christians, especially in the elementary programs. (Not unrelated, these elementary student teachers were also overwhelmingly white, middle-class and female which is worthy of separate consideration.) Their numbers were much greater than their presence in wider society and supported widespread reports of evangelical pastors exhorting their teenage flock to choose teaching as a career.
These are of course the people who are today middle and senior managers in schools and districts, and provide the pools from which principals and superintendents are drawn. How common this is I do not know, but I do know that it is happening.
Alongside the makeup of our teachers, a parallel situation exists. A friend of mine is at a school where three six year-old girls recently told a fourth that she was to burn in hell for all eternity. They were evangelical christians while the fourth little girl was a buddhist. At the same school, a parent told a teacher she was eternally damned. The parent, who was unrelated to those three children, was an evangelical christian and the teacher was catholic. Meanwhile, the PTA President and the school's outreach officer opened planning meetings with prayers, despite the presence on that particular school committee of teachers who objected. The PTA President and outreach officer are both evangelical christians.
This would be bad enough, but the story gets worse. The principal raised these and other matters with the board chair as she knew she needed his support before acting. However, he saw nothing wrong with any of what was happening. He too was an evangelical christian. He subsequently expressed his lack of support for the principal and his view she was not competent at board meetings and to parents. The principal ended up resigning, despite having taken a failing school and making it A+ and pre-dating the board chair by almost ten years.
But wait, there's more. It emerged that the board chair had told some parents that "the lord puts atheists in the path of believers to test them." He had two motives in wanting the change the school leadership: to create a school climate conducive to his religious views and to remove anyone in the way. Presumably his place in heaven is now assured.
To me, this is the same as the "Islamic Trojan Horse"stories. Both these muslim and christian groups are working behind the scenes, surreptitiously and even deviously, regardless of whether they are formally organized or things just organically happen.
Religious people and programs may have their place in schools sponsored by churches / mosques / synagogues. This is a societal question and not strictly educational. Religious people and programs have no place in our public and secular private schools.