Thirteen Boston University students, along with 1000 balloons and a banner-carrying airplane, demonstrated yesterday at B.U. against driver rudeness and the dangers of the Commonwealth Ave.-B.U. Bridge intersection.

The demonstrators obtained more than 300 signatures on a petition asking the city of Boston to post signs stating that the intersection is dangerous, Cheryl R. Tepper, a B.U. student and director of the demonstration, said yesterday.

Before circulating the petition, the demonstrators, members of a course in publicity at the B.U. School of Public Communication, surveyed Boston drivers to determine which intersections were considered the most dangerous. Respondents believed the Commonwealth Ave.-B.U. Bridge intersection is one of the three most dangerous intersections in Boston, Diane Donatio, one of the demonstrators, said yesterday.

Driver Rudeness

The protesters carried signs saying "Good Drivers Wave," "We Protest Driver Rudeness," and "Don't Tailgate." Before the demonstration, which took place from 8 to 10 a.m. and 12 to 2 p.m., the demonstrators tied 1000 balloons to the B.U. Bridge.

The demonstrators also displayed signs at the Cadillac agency located at the intersection and hired an airplane to fly over Boston carrying a banner reading "Drive Politely--A Little Courtesy Won't Kill You." The plane flew over Harvard and Fenway Park during the afternoon.

Tepper said the demonstrators used grants from about 45 co-sponsors, including the John Hancock Insurance Co.