Follow CBSDFW.COM: Facebook | Twitter

PLANO (CBSDFW.COM) – Students and teachers at Shepton High School in Plano returned to classes early Monday after a weekend of mourning. A car crash on Friday night claimed the lives of two 16-year-old girls, and a third teenage girl was badly injured during the incident.

READ MORE: Texas Attorney General Ken Paxton Sues Google Over Radio Ads For Smartphone

All three of the girls were students at the school, a campus for ninth and tenth graders. Grief counselors were on hand over the weekend, and were there again on Monday. The fatal crash was on everyone’s mind as students returned to class without three of their peers.

Many students left messages and tributes in chalk on their way into the school building.

READ MORE: Homeowner's Death Brings Scrutiny To Emergency Services In Prosper Area

Samantha Sacks and Lilly Davis died when the Porsche SUV that they were in caught on fire after crashing into a median and a tree along Mira Vista Boulevard at around 11:30 p.m. on Friday night. First responders found Kendall Murray on the ground outside of the vehicle.

An unidentified bystander pulled Murray from the backseat of the burning vehicle, saving her life. The teen was rushed to the hospital. She suffered third-degree burns and injuries to her pelvis and arm, family members said.

Murray had surgery on Sunday, and her mother posted an update on Facebook. “Good news… Kendall was finally able to open her eyes and squeezed my hand on command. The feeling was such a relief,” the post said. “We pray for the families that have lost their precious little ones, my heart hurts for all. Please continue to help through your prayers, which have meant so very much to our family.”

MORE NEWS: Bush Institute Expert: North Texans Should Care About What Happens In Ukraine

Friends gathered to remember Sacks and Davis over the weekend, and pray for Murray’s recovery. The three girls were all said to be very close to each other. Authorities are still investigating how the crash happened. They have explained that the Porsche was speeding when the driver lost control. It could be another week before the investigation is complete.