This study evaluates the effect of virtual reality and accommodation relax technique on controlling onset and development of myopia in school-aged children. Half of the children will receive head-mounted video display which shows video with virtual reality and accommodation relax technique in combination, while the other half will receive no intervention.

Inclusion Criteria:

• Best corrected visual acuity >=20/20 for each eye;
• Astigmastism less than 1.5 D;
• Anisometropia less than 1.0D;
• No other ocular or systematic diseases;

Exclusion Criteria:

• Can not endure virtual reality video;
• Can not cooperate with ocular examinations;
• Receiving other interventions for controlling myopia;