Who is "Jackie" in the movie "My Girl" (1991)?

Do you recall the scene in Mr Bixler's Adult Poetry class? There's a scene where Rhonda and Justin take everyone's hands and begin their spiritual work. Just before they begin to hold hands, a woman says, "That's really cool!". That woman is Jackie.

Find that scene, pause that scene and look at a pic of Nancy Chlumsky. It's her.

This really should be on the movie's Trivia page on IMDB.

From the movie script linked above (She's listed as "WOMAN" as I've pointed out below):

 SUMMER WRITING CLASS DAY

                              MR. BIXLER
             Before the class started, Ronda and Justin 
             wanted to lead the class in a group 
             meditation.

 Jackie -->  WOMAN
             Ooooh that's really cool.

                              JUSTIN
             Okay what we're gonna do is, send our vibes 
             out into the group.

     Justin turns on some kind of tape deck which begins to play 
     weird music

                              RONDA
             Everybody hold hands, and close your eyes. 
             Relax your muscles and take deep breaths.

                              JUSTIN
             Now, try to feel what the other person is 
             feeling, without speaking any words, send out 
             your vibe, and receive the vibes around you at 
             the same time. Can you feel it?