Before all of you junior crusaders get your panties in a wad, there's not much basis to the suit, and it is from a fringe group. While religious imagery (including crucifixes, Star of David) is essentially inappropriate constitutionally in government and other public places, there is considerable authority and precedent allowing it to remain when it is embodied in a display that advances or represents a nonreligious purpose.
Excellent Kly. Also, I refer Board members to Van Orden v. Perry and McCreary County v. American Civil Liberties union. These SCOTUS opinions compare and contrast much of what Kly has eloquently stated above.