Pomona High School student Alexander Groen reacted to the murder of 10-year-old Jessica Ridgeway by creating a program that will rely on high school students to help protect younger children.

Groen, 16, and a member of his school’s student council, is asking students at five Jefferson County high schools — Pomona, Arvada West, Ralston Valley, and Arvada, all in Arvada, and Standley Lake, in Westminster — to stand watch at the end of each school day at 28 feeder schools in the area, he said.

They will be dressed in purple shirts donated by community members and emblazoned with the logo “Jessica’s Angels.”

So far his idea, spread by Pomona students on Facebook and by word of mouth, has resulted in $300 in cash donations and a pledge by T-shirt supplier Color Concepts Apparel to make the shirts at a reduced rate, Groen said.

“As we get more money from people we are putting that into tee shirts,” he said.

Pomona student council and National Honor Society members will kick off the program Monday afternoon, with participants standing watch at four elementary schools for about 30 minutes at the end of the day.

Groen expects kids from the other high schools to join in at other elementary schools as word about the program spreads.

Eventually, he said, he expects there will be 10 to 20 high school students standing watch at each of the 28 elementary schools.

“As high schools join we will send them a list of their feeder schools and their student councils will do what they need to do” to tailor the program for their fellow students, he said.

Ridgeway disappeared on her way to Witt Elementary in Westminster on Oct. 5. Her dismembered body was found in Pattridge Park an Arvada five days later.

The child’s favorite color was purple.

Tom McGhee: 303-954-1671, tmcghee@denverpost.com or twitter.com/dpmcghee