To calculate taxes for a school teacher, follow these steps: 1. Gather all income documents, including the W-2 form and any 1099 forms for additional income. 2. Calculate the total Gross Income by summing up salary and any additional income. 3. Determine the Adjusted Gross Income (AGI) by subtracting allowable adjustments, such as student loan interest. 4. Choose between the standard deduction ($13,850 for single filers in 2023) and itemized deductions, depending on which provides the greater benefit. 5. Subtract the chosen deduction from the AGI to determine the taxable income. 6. Use federal tax brackets to calculate federal income tax by applying the appropriate rates to the corresponding income levels. 7. Account for tax credits, such as the teacher credit of up to $250 for classroom expenses, to reduce your tax liability. 8. Calculate state taxes, considering local rates and deductions. 9. Compare the total withheld taxes from the W-2 form with your calculated tax liability to determine if you are owed a refund or if you owe additional taxes. 10. File your tax return by April 15 using Form 1040 and any required schedules, either electronically or by mail.