Lampley, who was named principal of Harris last summer after having worked previously in Williamson County, will continue to serve at Harris through June 30.
"The decision to move from Harris Middle to Rock Creek Elementary was a family one," said Lampley, in a written statement.
"Our short time in Bell Buckle has been a very happy one and the Bedford County community has been wonderful. Over the last 22 years, my family has been extremely supportive in my career path and in my choices to further my education.
"My new position in Franklin County is an opportunity to be involved with my community as both a parent and as a principal, which is very important to me and my family.
"I am looking forward to working for [Franklin County Director of Schools] Dr. [Rebecca] Sharber once again as a principal. I have had the fortunate experience to work under her leadership previously in Williamson County and value her vast knowledge of educational excellence and leadership for all students.
"It has been an honor to serve the students of Bedford County and I know our 'Eagles' are being left in good hands with the current administration, faculty and staff at Harris Middle School and under the caring leadership of [School Superintendent] Dr. [Ray] Butrum. I will miss our 'Eagles' but will know that they are always showing their 'Eagle Pride.'"
Lampley will succeed Sarah Walker, who is retiring as principal of Rock Creek.