I'm studying Materia Medica as part of my naturopathy degree. I really enjoy learning about the different constituents of the various herbs and have been experimenting with them by making tea. My favorite is: Equal parts rosemary, lemonbalm and skullcap - I keep a decent amount of this combo in a jar and use about a teaspoon per cup.
Both lemon balm and skullcap have a relaxing effect on the nervous system and are therefore good as sleep-aids and also as anxyolitics (for nervous conditions such as anxiety). Rosemary on the other hand, is energizing and beneficial for cognitive function. The overall effect of this tea combo is a relaxed yet alert and energized state - I love it, and find it's the perfect mood to be in for study.
-L x