The Girl Scouts of Eastern Massachusetts will hold its 10th annual STEM Conference and Expo in Waltham on April 30, in two sessions:  Grades K-5 will be 9AM-12:30PM, and Grades 6-12 will be 1:30PM-6PM. The organizers invite volunteers to apply to offer demonstrations or hands-on activities (5 to 30 minutes each) to engage Girl Scouts in STEM. For more information, contact Eileen Koury at ekoury@gsema.org.