Arlington school board member Michael E. Brunner has asked the board to consider increasing the mandatory credits for high school graduation from 18 to 20, possibly by boosting math and science requirements.

Noting that 52 percent of this year's graduating seniors took 23 or 24 credits, Brunner said the proposal is designed to improve academic rigor.

The school administrative staff has been asked to report to the board at its meeting Wednesday, June 16, outlining ways the proposal could be implemented.

State law requires only 18 credits for graduation, but allows localities to require 20. In Northern Virginia, only Alexandria requires 20 credits, although Alexandria and Fairfax County require two math credits. Fairfax also requires two science credits. Arlington currently requires one credit each in math and science.

Brunner's suggestion is the same as that recommended by a special panel studying secondary school consolidations. The mathematics advisory commitee and the advisory council on instruction also have recommended increasing the required math credits to two. The council also suggested hiking the minimum credits for a laboratory science from one to two.

In addition, Brunner suggested the board consider requiring six academic periods per day. Currently, students have to take only five of the six regular class periods, allowing them to come late or leave early if parental permission is granted.

Brunner said he believes there should still be some exemptions from a sixth period if a student has to work or is participating in special activities.