Any pupil is deemed an habitual truant who has been reported as a truant three or more times per school year, provided that no pupil shall be deemed an habitual truant unless an appropriate district officer or employee has made a conscientious effort to hold at least one conference with a parent or guardian of the pupil and the pupil himself, after the filing of either of the reports required by Section 48260 or Section 48261. For purposes of this section, a conscientious effort means attempting to communicate with the parents of the pupil at least once using the most cost-effective method possible, which may include electronic mail or a telephone call.