Qualifications and pay differ among the area school systems. All require current X-rays or TB tests. All jurisdictions need substitutes.

District of Columbia -- Must have a bachelor's degree with at least 24 credits in a teaching area (a subject taught in elementary or secondary schools), plus at least 6 hours of education courses. Pay: $40 per day.

Call Ms. Scott at 724-4050.

Prince George's County -- Need a high-school diploma. You must pick up application from a local school, be interviewed and receive recommendation from the principal. Pay: $25 a day for high-school graduates, $30.50 for college graduates.

Call Mrs. MacFarlan: 952-4686.

Montgomery County -- Need a bachelor's degree and either student-teaching experience for education majors, or 2 years' teaching experience for other majors.

Pay: $38 a day for short-term substituting, $51.10 a day for long-term assignment (over 10 days for the same teacher).

Mr. Walker: 279-3559.

Alexandria -- Must be a certified teacher. Pay: $30 a day, $40 for long-term assignments.

Mrs. Korte, 750-6265.

Arlington -- Regular substitutes must have bachelor's degree and be able to be certified. Auxiliary substitutes for 1-day-at-a-time must have completed 2 or more years of college. Pay: $30 a day, $60.15 per day for long-term assignments (over 10 days for the same teacher).

Mrs. Knight, 558-2731.

Fairfax -- Requires 60 semester hours or a bachelor's degree. Pay: $26.56 a day for non-degree, $28.92 per day for college graduates.

Mrs. Dixon, 691-2803.