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  When tax time rolls around, everyone begins looking for deductions as a way to lower their taxable income so that they will owe less tax and hopefully get back a larger refund check. High school teachers have a large deduction available to them specifically as teachers as well as other deductions that are applicable to teachers.
  
  

Educator Expense Deduction

• High school teachers often find themselves spending their own money to equip their classrooms with needed supplies and equipment. Because of this, the IRS allows high school teachers to deduct up to $250 (2010) for single filers or $500 (2010) if married filing jointly, for unreimbursed expenses that a teacher pays for books, supplies, equipment and other classroom needs. For health and physical education classes, the expenses must relate to sports. According to the IRS, teachers can deduct only the amounts that exceed the following: the interest on qualified U.S. savings bonds excluded from income because you paid qualified higher education expenses; distributions from a qualified tuition program excluded from income; or tax-free withdrawals from a Coverdell Education Savings Account.
  
  

Unreimbursed Business Expenses

• Teachers can deduct unreimbursed business expenses if they itemize deductions on Schedule A. The cost of conferences, workshops and teacher's union dues are all deductible expenses. You will only be able to deduct the amount of these expenses and any other miscellaneous expenses you have that are greater than 2 percent of your adjusted gross income that you report on Form 1040. According to the IRS, these expenses must be "common and accepted in your field of trade, business or profession" or "helpful and appropriate for your business."
  
  

Mileage

• Some teachers, particularly those of specialty classes, travel between schools to teach. If this is the case, a teacher can tally the miles traveled between schools during the day and take the current IRS mileage reimbursement rate. This amount would also be recorded as an unreimbursed business expense on Schedule A. You will also need to fill out Form 2106 to take this deduction.