Possible Clues:

• Study full of letters one may use to solve one's problems
• A broken leg requires support - letters here set out the problem
• High school subject
• The search for x?
• Numbers and letters branch of maths
• In seminar, be glad Boolean speciality is raised
• A learner gets fifty percent: needs support for study in class
• Problem class
• Course with unknowns
• Branch of generalised arithmetic