MARBLEHEAD – “I Walk, I Rock,” the Board of Health subcommittee program that encourages school children to walk or bike to school, is ready to try again this fall.Michelle Gottlieb’s subcommittee got off to a rocky start last fall when some parents, upset about the traffic accident death of Allie Castner, raised concerns about the safety of having children walk to school. As a result of those concerns the program was halted.Now the program is gaining momentum and Gottlieb said she and her subcommittee – Kelley Braun, Laura Plunkett, Penny Wigglesworth and Allie Castner’s mother, Julie Castner – plan to meet this month to plan ways of introducing the program to the community.Gottlieb will be inviting the subcommittee’s first male member to that meeting – Attorney Carl King, who told the Board of Health Monday evening that he is a committee long-distance biker who used to commute from Marblehead to Boston by bicycle and rides regularly with a group of bikers who include retired Judge Samuel Zoll. King offered his services as a classroom and road instructor in bicycle safety.Gottlieb told the Board of Health that this year the subcommittee will discuss its plans with the “relevant people” to create an understanding of the program’s purpose. One event under discussion is a fall fair at the Marblehead Community Center, featuring crossing guards and other safety speakers.