Manya Whitaker, PhD, Developmental/Educational Psychologist; Assistant Professor of Education; Educational Consultant
First, it is important to note that charter schools are public schools so I appreciate that your question positions them as such. Second, it is hard to discuss charter schools as a conglomerate because each charter school/charter school organization operates within the framework of their individual charter that has been negotiated with their local public school district. Some charters are college prep schools while others focus on fine arts or technology. The best way to evaluate charter schools is to compare their performance to the performance of traditional public schools in the same district serving a similar demographic at the same grade level (phew!).
If I were forced to say how charter schools might be improving the overall quality of public schools, I'd point to two things: innovation and academic support. Many charter schools have additional funds beyond those provided by the state and local property taxes. These additional funds are often used to supplement academic experiences with tutors, after school programs, and a more diverse curriculum. Further, because charter schools don't have the strict rules that traditional schools have in terms of scheduling, class sizes, etc., they can often structure their school calendar to include innovative enhancements to learning such as Saturday school, extended school days, field trips, and community-based learning opportunities among others. They also have more resources and leeway to experiment with different academic models like multi-age classrooms and different pedagogical techniques like inquiry-based learning. So for those reasons, charter schools have upped the bar in terms of what parents and families can expect to be happening in public schools.
But on the downside, charter schools are getting a bad reputation because they can only serve a portion of the population who wants to attend. Almost all charter schools admit students via a lottery, but some charter schools also include an extensive application and interview process that some say is designed to weed out students whom they perceive to be academic underachievers. Further, a lot of college prep charter schools have very strict discipline policies including zero tolerance. The high number of suspensions and expulsions have caused some parents to compare their child's charter school to a prison. Finally, charter schools are contributing to the increased number of unlicensed teachers in public schools. Because charters can make their own hiring rules, many charter schools hire teachers who have temporary licenses granted through alternative teacher preparation programs such as Teach for America. While these teachers have great intentions, they begin their career without the proper training, coursework and experience necessary to be successful teaching in the low income, racially and linguistically diverse schools in which they are most often placed. A lot of data shows that teachers without professional licenses have lower student outcomes than teachers with professional licenses.
So all in all, it depends who you ask what you will hear about how charter schools help or hurt the public schooling system. Just remember that charter schools are only one option among many when it comes to school choice.