Six insurgent candidates are challenging the stockholders' slate in next week's elections for the Harvard Cooperative Society's Board of Directors.

The six challengers are running against 11 Harvard and M.I.T. students, nominated by the Coop's stockholders for the 11 student places on the 23-member Board of Directors. The stockholders' nominating committee, headed by Charles P. Whitlock, associate dean of the College, nominated the original 11 candidates based on consultation with deans and House Committees.

"Last year I found it impossible to get textbooks, and thought the whole administration of the Coop was pretty inefficient," Paul A. Silver '72, one of the challengers, said yesterday. "Then the cut in rebates was announced the same day nominating petitions were due for the Board of Directors, and Idecided that maybe the Coop wasn't being run so well."

Silver also cited his opposition to the Coop's recent expansion and emphasis on home furnishings. "The whole point of going to the Coop is to get things cheaper than anywhere else, or at least to get a rebate," he said. "How many students go there to buy beds, or color televisions?"

The elections for Board of Directors are being conducted by mail. Ballots listing all 17 candidates for the student seats have been mailed to the Coop's 18,000 student members. They must be returned by November 14 to be tabulated.