The Boy Scouts of America states it’s position on religious principles in
Article IX, Section 1, Clause 1-4 of the Charter and Bylaws. Here’s some points drawn from the statement;

• The Boy Scouts of America does not define what constitutes belief in God or the practice of religion.
• The Boy Scouts of America does not require membership in a religious organization or association for enrollment in the movement but does prefer, and strongly encourages, member-ship and participation in the religious programs and activities of a church, synagogue, or other religious association. If a Scout does not belong to a religious organization or association, then his parent(s) or guardian(s) will be considered to be responsible for his religious development.
• The Boy Scouts of America respects the convictions of those who practice religion as individuals without formal membership in organized religious organizations. In a few cases, there are those who, by conviction, do not feel it necessary to formally belong to an organized form of religion and seek to practice religion in accordance with their own personal convictions. Religious organizations have commended the Boy Scouts of America for encouraging youth to participate in organized religious activities. However, these same organizations reject any form of compulsion to enforce conformity to established religious practices.
• If a boy says he is a member of a religious body, the standards by which he should be evaluated are those of that group. This is why the application for the Eagle Scout Award requests a reference from his religious leader to indicate whether he has lived up to their expectations. Throughout life, Scouts are associated with people of different faiths. Scouting believes in religious freedom, respecting others whose religion may differ from theirs, and in the right of all to worship God in their own way.

From the Guide to Advancement 2011 –

5.0.5.0 Religious Principles

From time to time, issues related to advancement call for an understanding of the position of the Boy Scouts of America on religious principles. In the appendix (section 11), see the Rules and Regulations of the Boy Scouts of America (article IX), and clause 1, Declaration of Religious Principle, from article IX in the Charter and Bylaws of the BSA. The following interpretative statement may help to clarify this position:

The Boy Scouts of America does not define what constitutes belief in God or practice of religion. Neither does the BSA require membership in a religious organization or association for membership in the movement. If a Scout does not belong to a religious organization or association, then his parent(s) or guardian(s) will be considered responsible for his religious training. All that is required is the acknowledgment of belief in God as stated in the Scout Oath, and the ability to be reverent as stated in the Scout Law.

There are a number of Religious Emblems Programs developed by religious groups  approved by The Boy Scouts of America to be worn on the official uniform. The various religious groups administer the programs. Check with your local council service center or contact the religious organization directly to obtain the curriculum booklets.
More information available at Scouting.org