Internal Revenue Service
Irs: How Taxes Evolve? Lesson Plan
This lesson plan will help students understand that the legislative process of enacting federal income tax laws involves formal procedures based on the Constitution and informal procedures that blend and balance various interests.
Annenberg Foundation
Annenberg Classroom: Sixteenth Amendment
Text of the 16th Amendment accompanied by an explanation. Site includes links to related resources.
Siteseen
Siteseen: Government and Constitution: 16th Amendment
Provides an explanation and summary of the 16th Amendment or Income Tax Clause that authorizes Congress to collect income taxes.