Prince George's County students have shown gains in functional reading ability in tests taken last fall as part of the Maryland Accountability Program, according to figures released this week by the county school superintendent.

According to the figures, last year's students in the seventh grade tested about three per cent better than the previous year.In 1976, 64.2 per cent of the students were able to answer 80 per cent of the items on the test, while in 1975 only 61.9 per cent were able to do so.

Eleventh grades improved by almost 5 per cent over the previous year's testing results.In 1976 the figure for eighth graders achieving competency was 86.3 compared to 1975's figure of 81.8 per cent.

The testing gains, according to Edward J. Feeney, superintendent of schools, are "a direct result of our efforts to improve the functional reading component of our instructional program."

Seventh and eleventh graders in the state as a whole showed slightly higher gains than Prince George's students.

Dr. Louise Waynant, coordinating director of instruction for the school system, said the lower county test results when compared to the state-wide figures shows a need to gie an even greater emphasis to functional reading as a part of the reading program.

To fill this gap, the county next fall will increase its emphasis on functional reading - the reading of the everyday material such as "supermarket ads, telephone books, or job applications - by introducing new materials and guidelines for both teachers and students," a county school spokesman said.

"Publishers now are beginning to come forward with materials aimed at functional reading skills, and we hope to start bringing some of those into our classrooms, getting them on our list of approved instructional materials," said Waynant.