The New Jersey 2011 Adequate Yearly Progress report revealed that 53% (n = 75) of state schools that failed to meet standards were put on a 'priority school' list. The 2015 priority school list consisted of 66 schools. In response, New Jersey created Regional Achievement Centers to provide collaborative professional development (PD) for effective instruction in the lowest performing schools. The purpose of this transcendental phenomenological study was to explore the lived experiences of priority schoolteachers regarding experiences with past PD initiatives and PD under the current Elementary and Secondary Education Act flexibility waiver focusing on collaborative approaches that include job-embedded coaching and teacher networks. The research questions were germane to attempts to address failing schools through PD. The conceptual framework guiding the study was Fullan's educational change theory in which teachers learn by collaborating with other teachers and coaches. Through snowball sampling, 8 priority schoolteachers participated in semistructured in-depth interviews using an online conferencing tool. Data were analyzed by Moustakas' modified version of van Kaam's method. Participants did not perceive that past PD attempts addressed the needs of failing schools. Key findings regarding job-embedded coaching and teacher networks were that support given by coaches strengthened the participants' instructional practice, and teacher networks enabled the participants to collaboratively learn from each other. Positive social change may occur as district and school officials include teachers in PD planning. Adapting PD in this manner may improve implementation of PD initiatives for classroom instruction to increase student achievement.