D.C. Mayor Muriel Bowser, left, and former D.C. schools chief Antwan Wilson. (Jahi Chikwendiu/The Washington Post)

It was supposed to be a day like any other for Amanda Alexander. The District’s chief of elementary schools ran 3½ miles on the treadmill and arrived at work with plans to visit two schools and meet with some of her ­deputies.

But then Mayor Muriel E. Bowser (D) summoned Alexander in the morning with a startling question: Would she be willing to run the entire D.C. Public Schools system?

Chancellor Antwan Wilson was being forced to resign, and Bowser needed someone immediately to take charge for the rest of the school year.

Alexander accepted and, by late Tuesday afternoon, became interim chancellor of a system engulfed in two scandals, one involving graduation policy and the other the school lottery.

“I was surprised because it wasn’t something I was expecting, but I am excited to make sure that we stay the course here,” Alexander said in an interview Wednesday. “I am very capable of keeping things in the right direction.”

Amanda Alexander, the Interim Chancellor for the District of Columbia Public Schools. (N/A/DCPS)

With Alexander, the District gets a veteran of its schools system and a leader whose career has focused on instructional and curriculum development.

Alexander had applied to ­replace Kaya Henderson when she left the chancellor’s post in 2016, according to a Bowser administration official not authorized to discuss the matter publicly. But she was passed over for Wilson, who led the District’s schools for just one year and resigned this week after revelations that he skirted the city’s competitive lottery system so his daughter could transfer to a high-performing school. Deputy Mayor for Education Jennifer Niles, who helped Wilson circumvent the lottery rules, resigned last week.

“She is stepping into a situation that is unenviable, to say the least,” said Patricia McGuire, president of Trinity Washington University and co-chair of a community committee in 2016 that helped select Wilson. “The community is very upset right now, and being supportive of an interim chancellor is important so we don’t waste any time. There are too many problems to fix.”

Alexander, 42, started her career in 1998 as a kindergarten teacher in the District. She left for New York for two years before returning to the nation’s capital, where she served as principal of Bunker Hill and Ross elementary schools. At Ross, test scores rose dramatically under her watch.

In 2013, Alexander was tapped by Henderson to serve as deputy chief of schools and rose to chief of elementary schools a few years later. In her most recent role, she oversaw the city’s elementary schools and supervised six instructional superintendents who managed and mentored the lower school principals.

Alexander said she has not considered whether she will apply to be chancellor permanently.

Educators who work with Alexander said she scrupulously studies school data and uses it to establish plans aimed at improving teacher and student achievement.

“She has been consistently working toward having strong instructional practices in all the classes, and she has strong expectations for all the boys and girls and holds people accountable,” said Mary Ann Stinson, principal of Truesdell Education Campus in Brightwood. “She has a strong belief in equity and making sure there is equity throughout the city.”

Alexander said she has no plans for dramatic shake-ups, and is focused on leading the city to a smooth finish of the school year.

But part of her mandate will include addressing the findings of a damning city-commissioned investigation released last month.

The investigation discovered 1 in 3 graduates in 2017 missed too many classes or improperly took makeup classes, undermining the validity of hundreds of diplomas. The report also uncovered a culture of pressure in which teachers felt compelled to graduate unqualified students so that lofty graduation goals could be met.

“My takeaway is that there were some systems and procedures that were lacking . . . and that’s the work that we are focused on now,” Alexander said. “I think [D.C. Public Schools] has a great culture, but that’s not to say there are not areas that need improvement.”

While Alexander’s experience is mostly at the elementary level, she said she believes her two decades in education will allow her to tackle serious challenges facing the city’s high schools.

Test scores have improved in the district’s elementary schools, which are seen as a bright spot in the city’s education system. Still, education watchdogs said they believe there is a lack of rigor and discipline in elementary schools, which puts students on a path toward failure in high school.

Natalie Wexler, a D.C. education blogger, said lower-performing elementary schools are focusing on basic reading and math to boost standardized test scores — at the expense of a more ­well-rounded education that would help students think critically.

“What they are focusing on is just reading and math skills all day long — that apparent success is really sowing the seeds of failure in high school,” Wexler said.

Richard Jackson — a former D.C. high school principal who heads the Council of School Officers, a union for mid-level leadership in the school system — said he hopes Alexander looks to experienced high school leaders to help fix problems at the secondary level.

And after a period of upheaval in the school system’s leadership suites, Jackson said he hopes people rally behind Alexander.

“People are really rooting for her so that at least she can be a stabilizing force so there can be a level of normalcy,” Jackson said. “We don’t have anyone else to fire, so let’s do the work.”