It's similar to when people ask us why we don't test people instead of plants. It's because we want to do rigorous testing of prayer on simple subjects to establish a quantifiable relationship between the prayers and the results. How a quantifiable relationship can be established in a school setting is the foremost scientific problem to be solved. As a starting point for any researcher, silent prayer would be preferable to verbal prayer because of the religious bias and political controversy caused by verbal prayer. It takes many volunteers and some paid staff including a statistician.
Enormous funding is necessary for testing a school prayer hypothesis.
Spindrift Research is one of the sponsors of an outstanding annual conference on consciousness research. Explore the scientific and spiritual dimensions of consciousness. Dr. Dossey also wrote The Re-Invention of Medicine and Space, Time and Medicine. When more of humanity realizes that their thoughts actually do affect material conditions, this realization will cause a variety of psychological reactions. Some people will be angry to find out that their consciousness interacts with the environment and affects it.