What is the ruling on a student not praying Fajr due to fatigue and inability to sleep?

A Muslim must wake up for Fajr prayer, for prayer is the greatest pillar after the Two Testimonies, and a Muslim should not be lenient with it. If one takes the means to wake up (such as setting an alarm) but does not rise, there is no sin upon him. However, whoever deliberately abandons it is sinful, and fatigue is not an excuse.