President Reagan meets with small-business leaders on tax revision.

*Public Citizen sponsors a debate on tax policy between Robert S. McIntyre, director of federal tax policy for Citizens for Tax Justice, and tax lobbyist Charls Walker. The event begins at noon at the Hotel Washington. Phone 293-5083.

*Clarence Thomas, chairman of the Equal Employment Opportunity Commission, holds a news conference to discuss the commission's first decision on comparable worth. The briefing begins at 1 p.m. in Room 200C of the agency's headquarters, 2401 E St. NW.

*The Bureau of National Affairs releases a report on the increasing use of consultants in union-management battles, at 10 a.m. at its office at 1231 25th St. NW.

*The National Parent Teacher Association's convention continues at the Washington Hilton Hotel. TUESDAY

The Attorney General's Commission on Pornography begins three days of meetings and hearings at 10 a.m. in Conference Room B of the Justice Department. Wednesday's session is scheduled to start at 9:30 a.m. and Thursday's at 8:30 a.m., both in the Great Hall of the department.

*Reagan meets with Tunisian President Habib Bourguiba and the chairmen of the Coalition on Tax Reform. WEDNESDAY

The president flies to Indianapolis to address the annual national convention of the Jaycees and speaks to a luncheon meeting of the Chamber of Commerce in Mooresville, Ind.

The Center for National Policy sponsors a panel discussion on Disinvestment and South Africa, beginning at 7 p.m. in the ballroom of the National Press Club. Phone 293-1080 for reservations.

New York Gov. Mario M. Cuomo addresses the National Press Club at a 12:30 p.m. luncheon. THURSDAY

The Bureau of Labor Statistics issues its report on May consumer prices and real earnings. The president presents the Medal of Freedom to Mother Teresa and honors the 1985 Presidential Scholars, 141 distinguished graduating high school seniors.

*Arlene A. Triplett, associate director for management at the Office of Management and Budget, speaks at an 11:30 p.m. luncheon of the Association for Federal Information Resources Management at the Westpark Hotel in Rosslyn. For reservations, contact Shirley Page at 447-3152. FRIDAY

Reagan continues to stump for his tax-overhaul plan, this time in Dallas at the annual international convention of the Lions Club.

The American Petroleum Institute holds a briefing at 10 a.m. at 1220 L St. NW to discuss industry's efforts to comply with the Environmental Protection Agency's regulations for eliminating leaded gasoline.