The fact on which the two sources disagree is:
"There are too many people in a school district to follow one plan."
Source 1 suggests that the participation of many people in school districts is necessary for recycling to be effective, implying that their involvement can lead to positive outcomes. In contrast, Source 2 points out that getting all students to follow a specific recycling program may not be easy and could lead to ineffectiveness, suggesting that the large number of participants poses a challenge.