Prolific David Christensen joined the Lab School faculty as an elementary teacher in 1974. Eighteen years later, he won the Presidential Award for Excellence in Science and Mathematics Teaching, the first of three such Awards for Lab School teachers. This national Award was created in 1983 to recognize excellent teachers and encourage highly qualified individuals to enter and remain in the field. Christensen was honored in April 1993 in Washington D.C. in a ceremony hosted by President Bill Clinton. The Award included a $7,500 grant from the National Science Foundation to be spent at Christensen’s discretion to supplement Lab School programs. 

Christensen insisted that elementary students are excited about science. “I believe science must be experienced, not just read about,” he said. “Development theory shows that young children learn best through concrete experiences. As a result, nearly every science period I teach includes activities.” 

Christensen’s students credited him with increasing their interest in math as well as science. In 1980, Christensen partnered with Finsand in metric education by serving as editor of a new national metrics newsletter published by UNI. The newsletter was part of a $138,443 U.S. Office of Education grant, and was designed to keep people informed about a project called SITES (SI the international symbol for metrics; TES, Teacher Education Support). Some 60,000 newsletters were distributed each month. Beyond the newsletter, Christensen and Finsand offered a hot-line phone service for metric education projects across the country and for the coordination and dispatch of on-site consultants. “Anyone interested in metric education was encouraged to use the service to offer or to find assistance and resources on specific metric education problems,” Christensen explained. 

In 1993, the National Science Foundation selected Christensen to produce science teacher development modules. In 1998 and 2002, he was part of 7-week science programs for elementary and middle school teachers from Chile, supported by a grant from Chile’s government. The teachers visited Christensen's and other Lab School classrooms.