Here, in an essay written exclusively for PEOPLE, he remembers his two children, and talks about where he goes from here.
"My children Calyx and Beau were typical kids who lived exceptional lives. They were bright and happy, admired by all who came in contact with them. Like most kids their age, they loved their friends, school and sports – two all-American children in every aspect. However, through growing up in many different parts of the world, they developed many special qualities.
"Calyx excelled in her advanced classes and sports, especially track and cross country. She was a huge fan of Harry Potter; she even started a club at school. She was also friendly and outgoing, having been the 'new kid' in numerous schools. Calyx challenged everyone around her to think about others. She worked tirelessly to help her school raise money for the American Cancer Society, and she often spoke of her intense desire to 'do something that would change the world.' It's my goal that Calyx still will.
"Beau was all boy. He was proud to have just made the soccer team for his school. While his love was soccer, his friends were his passion. He and his buddies were silly, fun loving and friends for life. Beau had an incredible gift of empathy for others, even seeking out new kids and bringing them into his group. What I will remember most about Beau is his infectious smile and innate sense of humor.
"I forever will miss my two beautiful, loving kids. To help cope with my loss and have their incredible spirits live on, I am dedicating the rest of my life to honoring my children. I will remain involved in the activities that were important to them and support causes in which they believed. Friends of mine already have helped me begin my journey by establishing a memorial fund in their honor. The entire proceeds of the fund will be used to improve the lives of others, a standard by which my kids lived.
"I encourage others, especially those who join me in mourning Calyx and Beau, to help keep the essence of their spirits alive by being kind to others, by working and playing hard, and by living their lives with purpose."
Aanyone wishing to honor Calyx and Beau Schenecker can contact the Calyx and Beau Schenecker Memorial Fund within The Community Foundation of Tampa Bay at 550 N. Reo St., Suite 301, Tampa, FL 33609-1037.
For more on the Schenecker story – including several never-before-seen pictures of the family – pick up this week's issue of PEOPLE, on newsstands Friday