To his friends, Sebastian Bull was the one you'd least expect to become an educator.
"I'm pretty shy, so when I told (my friends) I was going to get my credential to be a teacher and go into education, they thought I was nuts -- there's no way I can hold a conversation with a student or run a class," Bull, 45, said in a recent interview.
"It's fun to prove them wrong," the new Foothill High principal added with a laugh.
After spending his first 11 years in education teaching social studies at Amador Valley High, Bull became an administrator, serving as a vice principal at the school for five years.
In July 2015, he was appointed principal of Donlon Elementary. Bull was nearing the end of his second school year at Donlon when then-principal Jason Krolikowski announced he was leaving Foothill to become the next head of San Ramon Valley High -- and leaving a vacancy to be filled at the Pleasanton school.
Interested in moving back into high school administration and staying in PUSD, Bull applied for the job and was appointed principal of Foothill in May.
"I wasn't really ready to leave Donlon because I was enjoying it, but I thought if I wanted to get back to high school this was probably the best time because who knows how long it'll be until there's another high school opening, especially if I wanted to stay in Pleasanton," Bull said.
"I didn't want to move out of the school district because I care about this place and want to make sure schools are running well, kids are taken care of and staff are happy," he added.
Born in England, Bull's family moved to Southern California when he was 7 years old.
It was in middle school that the idea of becoming an educator first took hold.
"In seventh grade I had a math teacher, and I don't think the teacher was very good," Bull recalled. "I remember sitting in the back of the class thinking, 'I don't really know math very well or like it, but I could do a better job than this teacher.'"
"And then the next year, in eighth grade, I had a U.S. history teacher who was phenomenal," he continued. "Since I had the seed planted the year before about what not to do and then I saw his class which was what to do, I thought, 'This is a cool thing.'"
Upon obtaining his bachelor's degree in geography from UC Santa Barbara, Bull moved to the Bay Area in 1996.
After earning his teaching credential from Mills College, Bull applied to social studies teacher openings in 15 school districts.
He was interviewed for two of them -- one at Concord High and the other at Amador.
Bull was offered the job at Amador and he accepted, kicking off what would be a 16-year tenure at the school.
His move to the rival Foothill was met with some good-natured ribbing from former Amador colleagues, although Bull says his wife Amy -- a science teacher at Amador -- "has been very good about it."
"I did have a visit from a former staff member here at Foothill (athletic director Tom Hansen) who showed up at Donlon with a garbage bag to help me get rid of my purple stuff," Bull said.
"It is strange to go from Amador to this school after being at Amador for so many years, but it's been nice," he added. "Both schools are pretty amazing. There's some similarities but some differences, so it's cool to have that comparison."
As an administrator, Bull describes himself as a "service leader."
"I like to help people and support people and to roll my sleeves up and get my hands dirty," he said. "I'm more than happy in helping move things around campus or picking up garbage after lunch just because I care about the place."
Bull lives in Pleasanton with his wife Amy Turner Bull -- the two met as teachers at Amador -- and their two sons ages 5 and 7.
Together they enjoy taking part in sports and traveling. Over the summer, the family visited Boston, New York, Vancouver and Alaska.
"It's great for our kids to be able to see different places and learn and meet people," Bull said.
In addition to his bachelor's degree and teaching credential, Bull also has an administrative credential from Cal State East Bay.
Bull earns an annual salary of $150,346 as principal of Foothill High, located at 4375 Foothill Road.