If you need to ask that question then you should stay away from children.
Why do you say that? Religion in school is only okay if it's a religion you like? Do you know anything at all about the Satanic Temple? Did you read your own article?
I'm guessing you didn't because if you had, your title would be different. The school isn't teaching anything, and a parent asked for the Temple to offer an opportunity, once a month, for students who choose not to attend Christian offerings, which are offered weekly. The "class" is offered off campus and is "not affiliated with or approved by the local school district or board members." Per your link.
Furthermore, the Satanic Temple, per your link, does not worship Satan, but they do seek "to strengthen students' critical thinking, good works in the community, compassion and empathy, self-directed learning and creative expression."
If you let one religion into schools, you have to let them all in. It's a case of "be careful what you wish for, you just might get it."
Except for elective courses on religious studies, religion has no place in public schools. Period, full stop.
As for you snide comment regarding my suitability to be around children, I believe the opposite to be true. Your apparent need to force your ideas, beliefs, and opinions on children that are not your own should disqualify you and your... "fiancee..." from ever reproducing. It's not your place, or anyone else's, to push your religious beliefs on anyone's children save your own.
I raised my children to think for themselves in all things, especially religion. Some go to church, some don't. They all are responsible adults who contribute to society rather than suck from its teat. I couldn't be more proud of them.