obsolete  in  a  short  time  because  of  changes  in policy,   equipment, or   procedures. Eight- millimeter   (8-mm)   single-concept   films   have replaced   16-mm   motion   pictures   in   many   in- stances because 8-mm films are less expensive to produce,  require  less  expensive  equipment  for presentation,  and  can  be  more  easily  geared  to present a single idea or concept. OTHER  AIDS The   audiovisual   field   is   becoming   increas- ingly sophisticated from the equipment or hard- ware   standpoint.   Technological   advances   have made available relatively inexpensive audio and video  tape  recorders  and  various  types  of  pro- grammers and synchronizers so that the chaplain and the RP can produce and present high quality audiovisual presentations. Audio Tape The   majority   of   audiovisual   presentations utilize  audio  tapes  to  some  extent.  A  combina- tion  of  prerecorded  audio  tapes,  usually  a cassette,  and  appropriate  35-mm  slides  is  called  a multimedia   presentation.   The   tape   track   or channel  is  recorded  with  the  narration  and  the change  signal  is  recorded  on  the  remaining channel.   After   the   tape   and   slides   are   coor- dinated,  the  audience  hears  the  narration  while the  recorded  synchronizer  sends  a  command  to the  projector,  and  changes  the  slides  at  the appropriate  place  in  the  narration. Video  Tape Cassettes   are   now   available   to   each audiovisual  library  that  is  equipped  with  the proper equipment (cassette player and monitor). The   video   cassettes   are   cost-effective   because they  can  be  reused  many  times.  The  use  of prerecorded  video  tapes  is  expected  to  save money  during  the  production  of  these  aids.  A minimum  of  motion  picture  prints  can  be  pro- duced  and  video  cassettes  can  be  recorded  for unexpected requests, then after the cassettes are no longer required, they can be erased and used for  a  new  subject. THE SELECTION AND USE OF AUDIOVISUAL  (AV)  AIDS Audiovisual   aids   are   valuable   tools   which can   help   RE   instructors   reinforce   religious education and make learning more interesting to students.  In  order  for  this  to  occur,  however, every RE instructor must know how to select the most  effective  AV  aids,  determine  which  audio- visual  aids  are  available,  and  know  how  to  use them  effectively. Inasmuch  as  audiovisual  aids  are  so  benefi- cial,  it  is  quite  likely  that  some  RE  instructors may  depend  too  much  upon  them  in  their classes.   The   RE   instructor   may,   in   fact,   con- clude   that   the   use   of   audiovisual   aids   can accomplish  practically  all  of  the  instruction,  but this  is  a  very  serious  misconception  about  the function   and   use   of   AV   aids.   RE   instructors must  be  taught  that  audiovisual  aids  are  used only  to  supplement  training.  Audiovisual  aids are designed to clarify and speed up instruction but they cannot take the place of the instructor. Some RE instructors mistakenly assume that the more  audiovisual  aids  they  use  in  their  classes, the  better  their  teaching  will  be.  Their  classes  can become a kind of juggling act, a frantic shuffling back  and  forth  from  one  type  of  training  aid  to another. A basic principle to bear in mind when employing audiovisual aids is that a few AV aids utilized well will have better instructional results than   a   confusing   array   of   aids   which   are presented  so  rapidly  that  sufficient  time  is  not given for the students to understand the material presented. How  should  RE  instructors  select  from among  those  audiovisual  aids  which  have  been approved  for  religious  education?  When  should audiovisual  aids  be  used  together  in  the  same lesson? The answer to these questions is that an audiovisual  aid  (or  aids)  should  be  utilized  only when   it   can   assist   in   achieving   the   learning objective. The following principles will guide the instructor  in  the  selection  and  use  of  the audiovisual  aids  which  have  been  approved  for use  in  a  command’s  religious  education  pro- gram: The  audiovisual  aid  must  be  reviewed  to ensure that the material it presents is relevant to 7-8