BOSTON – Former teachers of convicted Boston Marathon bomber Dzhokhar Tsarnaev testified at the sentencing phase of his trial for the defense, arguing he doesn’t deserve the death penalty.

“He was already rightly found guilty. I testified to help the jury see why he might be spared the death penalty,” Becki Norris, Tsarnaev’s seventh- and eighth-grade teacher – now principal at Community Charter School of Cambridge – posted to her Facebook page, according to the Huffington Post.

“I also hoped to show him, in spite of what he’s done, that someone cares about him as a person,” Norris wrote.

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Tsarnaev, 21, and his older brother, Tamerlan Tsarnaev, 26, detonated two bombs at the 2013 Boston Marathon finish line that killed three people and wounded 264 others. Tamerlan Tsarnaev also later killed a Massachusetts Institute of Technology officer and died in a shootout days later, Business Insider reports.

Dzhokhar Tsarnaev was found guilty by a jury in April for his role in the killings.

The younger Tsarnaev’s attorneys worked to convince jurors he was under the influence of his older brother, “a boxer turned aspiring jihadi,” during the bombing, according to the news site.

Tsarnaev’s fifth and sixth grade teacher at the Cambridge School, Tracey Gordon, also testified that the young student quickly learned English after moving to the U.S. from Russia, and his desire to learn was infectious.

“He was a person who you enjoyed being around,” Gordon said.

Tsarnaev would “befriend anybody and help anybody in need.”

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Two of Tsarnaev’s college friends also testified on his behalf, describing the aspiring marine biologist as a loyal friend, Business Insider reports.

“I really miss the person that I knew,” one friend said.

Another, Alexa Guevara, 21, said Tsarnaev “was just there for me” as she broke down crying during testimony, according to the news site.

Others who took the stand had a much less favorable view of the convicted bomber.

The Huffington Post reports:

Bombing victim Rebekah Gregory shared a widely circulated letter denouncing Tsarnaev as “a coward” who wouldn’t make eye contact with her while she testified in March about losing her leg from the attack.

“[N]ow to me you’re a nobody,” Gregory wrote, “and it is official that you have lost.”

Today, Norris posted a link to an expanded version of her thoughts on the case to her Facebook page.

“I have many pictures of a 12- and 13-year-old Dzhokhar. The one that still hits me right in the gut shows him smiling into the camera as he holds my newborn daughter. Dzhokhar is known to many as the younger, surviving Boston Marathon bomber,” Norris wrote.

“To me, he was a beloved advisee and student. Teachers encounter thousands of youth over the years, and a few find a special spot in our hearts. They stick there, unforegettable. Dzhokhar is one of those few.”