The Center on Reinventing Public Education has produced a short report titled, “Are Charter School Unions Worth the Bargain?” that contains some longed-for hard data on charter school unionization rates, where those schools are located, and why they are unionized – whether by law or by teacher action.

The report, authored by Mitch Price, also evaluates charter school collective bargaining agreements and concludes that while they tend to be more flexible than traditional district contracts, they also contain many of the same trappings. But in my mind the greatest value of the study is not in its analysis of contract quality, but in its series of graphs and tables with basic data about unionized charters.

This simple one, for example, has the number of unionized charters and the method by which they achieved it – using statistics provided by the National Alliance for Public Charter Schools:

Price adds that 44% of conversion charters are unionized, but only 9% of start-ups.

Charter schools that unionize through employee vote are a rarity, which might explain why such occurrences always get media play. Worrying about this becoming a trend or a movement is a waste of time and emotion. Just from a practical standpoint, unions will not spend money and manpower to organize a handful of teachers at a single charter school. If they have designs on increasing membership through charter employees, it’s much more likely to happen through a state mandate.