was found that there was no "excessive entanglement" since the buildings were themselves not religious, unlike teachers in parochial schools, and because the aid came in the form of a one-time grant, rather than continuous assistance. One of the largest recent controversies over the amendment centered on school vouchers—government aid for students to attend private and predominantly religious schools. The Supreme Court, in Zelman v. Simmons-Harris (2002), upheld the constitutionality of private school vouchers, turning away an Establishment Clause challenge. State-sanctioned prayer in public schools Further important decisions came in the 1960s, during the Warren Court era. One of the Court's most controversial decisions came in Engel v. Vitale in 1962. The case involved the mandatory daily recitation by public school officials of a prayer written by the New York Board of Regents, which read "Almighty God, we acknowledge our dependence upon Thee, and we beg Thy blessings upon us, our parents, our teachers and our Country". The Supreme Court deemed it unconstitutional and struck it down, with Justice Black writing "it is no part of the official business of government to compose official prayers for any group of American people to recite as part of a religious program carried out by the Government." The reading of the Lord's Prayer or of the Bible in the classroom of a public school by the teacher was ruled unconstitutional in 1963. The ruling did not apply to parochial or private schools in general. The decision has been met with both criticism and praise. Many social conservatives are critical of the court's reasoning, including the late Chief Justice William H. Rehnquist. Conversely, the ACLU and other civil libertarian groups hailed the court's decision. In Abington Township v. Schempp (1963), the case involving the mandatory reading of the Lord's Prayer in class, the Supreme Court introduced the "secular purpose" and "primary effect" tests, which were to be used to determine compatibility with the establishment clause. Essentially, the law in question must have a valid secular purpose, and its primary effect must not be to promote or inhibit a particular religion. Since the law requiring the recital of the Lord's Prayer violated these tests, it was struck down. The "excessive entanglement" test was added in Lemon v. Kurtzman (vide supra). In Wallace v. Jaffree (1985), the Supreme Court struck down an Alabama law whereby students in public schools would observe daily a period of silence