Family and friends say Charlie and Braden Powell were fun-loving little boys who were "full of life" and adapting well to their mother's disappearance.

Throughout this week, we've heard a lot about Josh Powell's evil murder of the little boys, his suicide, and the 9-1-1 call before the tragedy. We haven't heard as much about the young victims who heard their dad say he had a "big surprise" for them, before he killed them.

Dean Curry, lead pastor of Life Center Church in Tacoma, says today's memorial is a time to remember "two beautiful boys, works of art," and to set aside the anger and acrimony associated with the circumstances of their deaths.

About 2,400 attended the service and heard Charlie's kindergarten teacher described him as "the little scientist." He loved reading nonfiction, which he called "real books." Classmates loved him, she says. Preschool teachers say Braden liked going to the zoo, playing with trucks, puzzles and building things. "He smiled a lot and told great stories," says one of his former teachers.

They were typical boys. Charlie asked for a pet goldfish for his birthday. They liked to play the boardgame Candy Land and pick fruit from their grandparents' garden. They loved books and they were excited by going on new adventures.

They had also taken classes at the YMCA, where they participated in a martial-arts program.

Social worker Elizabeth Griffin-Hall, who took the boys to Josh Powell's home for a supervised visit not knowing they were going to their deaths, talked about the boys for an ABC News "20/20" special last night. Griffin-Hall says she has sweet memories of the boys.

"I loved the boys. I was like a grandma to the boys. They crawled all over me," says Griffin-Hall.

Braden, who was just 5, "was a free spirit" who "smiled all the time," she says. "He was always making things and giving them to me."

Seven-year-old Charlie "was smart and funny. He loved bugs and frogs. He had a bird." Charlie was looking forward to having his own frog pond when he moved back with his dad, she says.

"They are not going to grow up," Hall told ABC News. "They're not ever going to look at bugs and frogs again."

A Facebook memorial page photo of Susan Powell with her boys Charlie and Braden. Susan was last seen in December of 2009. The boys died in a fire at their father's home Sunday. Josh Powell killed his boys and himself in the blaze that was intentionally set.

Chuck and Judy Cox walk past the casket of their grandsons and a public memorial in Tacoma. The boys' bodies will be buried together in a single casket during a private funeral . AP photo

A memorial fund has been set up in memory of Charlie and Braden. Donations can be made to The Charlie and Braden Powell Memorial Account at any Western Washington Wells Fargo bank branch.

By Linda Thomas