Among the parent education workshops offered in Washington area:

"Parent Sex Education " -- Under a federal contract, MATH-TECH (a research consulting firm) coordinates free classes geared to helping parents become the primary sex educators of their children. Classes will be run at the Psychiatric Institute of Washington for parents of 11- to 18-year-olds; Family and Child Services in Northwest for parents of 3- to 6-year-olds, and George Mason Junior/Senior High School in Falls Chruch for parents of 10- to 18-year-olds. Call 657-1610.

"Adolescent Sexuality" -- Part of a free, three-part series on adolescent health issues offered from 7 to 8:30 p.m. Nov. 5 at Georgetown University Hospital. 625-2831.

"Communicating With Adolescents About Sexuality" -- A 4-week course scheduled for January at Cedar Lane Unitarian Church, $30 for non-members and $25 for members. 942-3802.

Etc . -- A group of Washington-area sex educators who conduct workshops and offer consultation on teaching human sexuality. 654-6655. Reading

The Sex Education Coalition's Deborah Hollander recommends these books for reading aloud with pre-school and elementary-school-age children: Age 4 and Up

"How Babies Are Made ," by Andrew Andry and F. Schepp (Time-Life). Explains plant, animal and human reproduction.

"Did the Sun Shine Before You Were Born ?" by Sol and Judith Gordon (Edu-Press). Discusses the love between members of different kinds of families.

"How a Baby Is Made ," by Per Holm Knudsen (Franklin Watts). Highlights the love between parents. Age 5 and Up

"Made to Grow ," by Robert and Annell Harty (Broadman Press). Offers information within a religious framework.

"Mommy, Where Do Babies Come From ?" by Simone Zapun (Platt and Munk). Teaches how flowers, plants and people reproduce. Age 6 and Up

"The Body Book ," by Claire Rayner (Barron's Educational Series Inc.). Includes such basic topics as why people burp, urinate, sneeze. For Parents

"The Parent's Guide to Teen-Age Sex and Pregnancy," by Howard and Martha Lewis, (St. Martin's Press).