Teachers who knew Boston Marathon bomber Dzhokhar Tsarnaev as a child described him as a hardworking youngster who seemed to have a bright future.

Catheryn Charner-Laird, his third-grade teacher, said Tsarnaev was just learning English after moving to the U.S. from Russia in 2002 and cared very much about his school work. She said he "always wanted to do the right thing."

Other teachers said he got nearly all As in his classes, made friends easily and was an excellent soccer player.

The testimony came Wednesday during the third day of the defense case in the penalty phase of Tsarnaev's trial. He was convicted earlier this month in the 2013 bombing that killed three people and injured more than 260.

The same jury is now hearing evidence to decide whether he should be sentenced to life in prison or the death penalty.

Tsarnaev's lawyers on Wednesday shifted the focus away from his older brother, Tamerlan, who they have portrayed as the mastermind of the attack and a domineering influence on Dzhokhar.

Prosecutors have said the brothers were partners in the bombing, which was designed to retaliate against the U.S. for its actions in Muslim lands.

Rebecca Norris, one of Tsarnaev's teachers in seventh- and eighth-grade, said he was very bright and well-behaved.

"He wasn't a rebel. Basically, if you asked him to do something, he would do it," she said.

Norris said Tsarnaev was one of the school's best students and soccer players.

"I thought we would get him into a really good college with a full ride, and he would be very successful," she said.

The defense also showed the jury two photographs of a cherubic-looking Tsarnaev when he was about 9 years old. In one photo, he is sitting on a bench next to Tamerlan, who is about 16. Tamerlan has his arm around him, while Dzhokhar rests his arm on his older brother's leg.

In the other, Dzhokhar is smiling with his mother, two sisters and the landlady who owned the Cambridge apartment building where they lived.

Jurors also heard from two paramedics who treated the Tsarnaev brothers after a firefight with police in Watertown days after the bombings.

Paramedic Michael Sullivan said Tamerlan Tsarnaev was combative after being shot by police and run over by Dzhokhar during a chaotic getaway attempt. Sullivan said Tamerlan "would lift himself off the stretcher and yell and scream and try to resist us touching him."

He said sometimes people in shock react that way. Tamerlan was later pronounced dead at the hospital.

Paramedic Laura Lee said Dzhokhar was awake and alert when he was put into an ambulance after being captured hiding in a boat in Watertown. He had a gunshot wound to his jaw, a leg wound and other injuries.

When someone put a tourniquet-like bandage on his leg, "apparently it was very tight and he was mad and it got loud," Lee said.

"He said, 'Where's my brother?'" Lee recalled.

Lee said someone else in the ambulance told him, "You'll find out soon."