CD-ROM PREVIEWS

["MACALPINE, JEAN" <JEAMAC@CLINTON-ELEM.MORIC.ORG>]

I am hoping to begin developing a CD-ROM collection next year.  I
think the difficulty is going to be having to buy blind, because most
companies don't allow previews.  Could any of you out there who have
purchased CD-ROMS for your libraries tell me how you decide what to
purchase?  Do you go by reviews, by word of mouth, exhibits, I'd
appreciate any information and advice you might offer.  Now, I'll ask
for your recommendations:  Can anyone recommend CD-ROM titles that
pertain to:
        Human Body
        20th Century History
        Plants
        Animals
All of these would have to be appropriate for 4th or 5th graders.
TIA, Jean MacAlpine