I am a big believer in starting rituals. They work. They pacify the brain and facilitate a change of behavior. Brain yoga has become my starting ritual for a long study session. If you want to uplevel your studying and grades, you have to change the way you study. You may need to study for longer period of time ( at least initially). Brain yoga will get your blood flowing, reset your brain to help you power through a long study practice.
I hope you enjoy this video: