Here’s the super short version: The Supreme Court basically ruled that public school employees may lead or participate in prayer with students, presuming of course said prayer is of a Christian variety.
Peter Greene explains more, including noting this particular clause of the decision in the Kennedy case:
In place of Lemon and the endorsement test, this Court has instructed that the Establishment Clause must be interpreted by “‘reference to historical practices and understandings.“‘[T]he line’” that courts and governments “must draw between the permissible and the impermissible” has to “‘accor[d] with history and faithfully reflec[t] the understanding of the Founding Fathers.’”
Jesus, Mary, Mother of God. As with previous uses, this "test" can be used to roll everything back! Brown v. Board, here we come!
Read the rest here.