"At this time we are mourning the tragic death of our amazing, beautiful daughter and sister," read a statement from Ritzer's family. "Everyone that knew and loved Colleen knew of her passion for teaching and how she mentored each and every one of her students."
Riley Doyle, 14, was a student in Ritzer's geometry class. She said that her teacher "was always really upbeat and positive and excited about math."
"She made every lesson like you wanted to learn it," Riley said. "For the first time, math became one of my favorite classes. She was always very courteous to her students, and she would never talk down to them. She treated them like people."
Riley's sister, Regan, didn't have Ritzer as a teacher, but she still had very positive impressions of the deceased teacher.
"My sister would always come home from school saying how she was her favorite teacher," Regan said. "It's just a tragedy, and it's so bad because she's so young and you could tell that she really loved her job and the kids, and it's sad that this had to happen."
Ritzer graduated from Assumption College in Worcester in 2011.
"The Assumption community will keep Colleen's family members in its thoughts and prayers during this time of great sorrow and loss," Assumption College President Francesco Cesareo said in a statement. "We pray that God will give them strength and comfort during these difficult days and commend Colleen to God's loving presence."
The Danvers school department released a statement about Ritzer's murder:
"Today, the Danvers Public Schools lost a dynamic and brilliant ray of light. Colleen Ritzer was everything one could ask for in a teacher -- dedicated, passionate and invested in her students. Our entire community will feel this loss for many years to come."
Swim Week Miami Beach 2014 [PHOTOS]