"Sometimes, I do a very good job on weekends being able to leave my job and be with my family and friends," said Kessler, superintendent of the San Ramon Valley Unified School District.
Then there were times he found himself "waking at 3 in the morning, essentially at work."
Now, Kessler, 60, plans to retire at the end of the school year, he announced to the school board last week.
The district academically ranks eighth in the state. Under Kessler's 13-year tenure, the district's schools have been renovated, academic performances have improved, and finances have been balanced.
"We've been lucky to have a superintendent to be as good as Rob," said Trustee Paul Gardner. "He's a great educator."
"He grasped the issues of school financing," he added. "He could make recommendations about educational value and could make recommendations on how we were going to pay for things."
Kessler, who lives in Albany, said he was leaving because he wanted to explore other life possibilities.
"The timing was right for me," he said. "We accomplished what we set out to do."
Currently, he teaches an educational leadership course for teachers and school administrators at California State University, East Bay. He is also looking into consulting and executive coaching.
"There are so many opportunities," he said.
He noted he has plenty of positive accomplishments in the district. Helping administrators and students solve problems, as well as developing trust and rapport with district constituents, are among his great achievements. In addition, several bond measures have been passed to upgrade and modernize schools. Also, schools have opened in Dougherty Valley under his leadership.
"He's got a lot to be proud of," said Trustee Greg Marvel.
He also created a public relations position, which is filled by Terry Koehne.
"The district never really ever had anyone to talk about the district and figure out partnerships," Kessler said. "The community has responded with a better understanding."
"Local Realtors will tell you one of the main reasons why people move here is because of the quality of schools," he added.
Kessler said he enjoyed being around an extraordinary group of staff members to solve problems.
However, he also faced a tremendous amount of pressure being head of a district that is a $200 million-per-year business with more than 2,500 employees, 26,000 students and well over 70,000 constituents. One of the biggest stresses he faced was the inadequate funding the district received from the state.
"We are continuously funding long-term planning and trying to figure out priorities for our money," he said. "We make tough decisions. We can't fund them (children) at the level we want. We are having to disappoint people."
Kessler also said special education has been a major issue.
"It's on the list of things that are major challenges for every school district," he said, adding that the district has made strides in improving its special education curriculum.
Additionally, narrowing the academic achievement and proficiency gaps between students are challenges. Although the majority of students do well, there are a significant number in general education that struggle in English and math. Teachers have found it difficult to provide the right instruction for them.
"Some of those questions are unanswered," Kessler said. "We tried to do all things. We all put our heads together and talk to each other."
Kessler grew up in Palo Alto and went to UC Berkeley in 1969 where he majored in political science, specializing in African Studies after his interest was piqued through a friend with an African background.
"It was intense political turmoil," he said. "Yes, I was involved in anti-war activity."
He did graduate work at Harvard in history but realized he would be stuck in academia - removed from much human interaction. He discovered he enjoyed working with people and solving problems, which prompted him to go into education. He went back to Berkeley and received his teaching credential.
He received his master's degree in curriculum and educational administration at San Francisco State University. He began his career in education more than 33 years ago as a fifth-grade teacher in Moraga.
He was the superintendent of schools for the Reed Union School District in Marin County. He joined the San Ramon Valley Unified School District in 1993 as director of certificated personnel. He oversaw all aspects of the employment process for teachers, principals, nurses and librarians. He was appointed by the trustees as superintendent in 1995.
The district plans to look at all qualified applicants for the vacated superintendent position and hopes to hire someone to replace Kessler in March or April. Marvel said he hopes the next superintendent will continue to push the district to be its best nationally and internationally.
"The board is very sad to see him go," Gardner said. "At the same time, he's moving on to the next phase of his life. The district will continue running well. Life goes on."
Kessler said the primary quality for the next superintendent is communication.
"It's not always an easy thing to do," he said. "The more people involved in the communication process, the more complex it is. It's ultimately why we are so strong as a school district."
Kessler's wife Sally Benjamin is a counselor at Albany High School. His son David graduated from UC Davis and is working in Boston as a union organizer. His daughter Julia is attending the University of Michigan and studying Arabic and Middle Eastern studies.
"They are too far from home as far as I am concerned," Kessler said.