Charters serve nearly 8% of public school students and the research on their effectiveness is overwhelming.
Some states have stronger policies than others, but it's not a stretch to say that charter schooling is the most effective K-12 reform in the last three decades.
Competition, and diversified a portfolio of choice policies, are good things.
Case in point: Arizona came within a whisker of seeing its ESA program downsized at the ballot.
Choice policies have tradeoffs, and ESAs have big advantages over charters. But we need them all.