Op-Ed: "Chicago Stories" Chicago has seen wars over charter school, Common Core, the opt-out movement, pensions and more.

Op-Ed by Sara Ray Stoelinga, originally published in U.S. News and World Report.

CHICAGO – For the past seven years, President Barack Obama and Secretary of Education Arne Duncan have been pushing an agenda of education ideas, many of which got hatched here in Chicago.

As the third-largest school district in the nation, serving about 400,000 students, Chicago has stories to tell and lessons learned for others around the country. Some of these stories are drama, verging on melodrama: The beleaguered mayor pitted against the teachers' union, sparring across picket lines. Charter wars, Common Core, the opt-out movement, pension debacles and more.

Here are four education ideas, insights and question marks from Chicago that are both reflective of key national debates in education and illustrative of lessons learned that can influence school improvement:

Secondary is just the start. In December, a study revealed that just 14 percent of Chicago public high school freshmen go on to get a bachelor's degree by their mid-20s. The good news is more Chicago students are graduating from high school, and more are enrolling in college. But a whole lot of those high school graduates are enrolling in colleges that have dismal institutional graduation rates.

Even among higher education institutions at the same level of selectivity, some colleges and universities are doing a better job of keeping students in college; some are also doing a better job of holding onto underrepresented minorities in particular. This is happening in a context where universities, state institutions in particular, are facing shifts in incentives and sanctions around institutional graduation rates. Historically, many colleges have received state funding based on how many full-time equivalent students are enrolled at the beginning of the semester. This model provides incentives for colleges to enroll students and thus provide access to postsecondary education, but this model does not necessarily provide incentives for institutions to help students successfully complete degree programs. Many states are reconsidering the enrollment-based funding model.

Greater scrutiny for higher ed is a nationwide trend, and Chicagoans are among those striving to make local institutions take notice and be more accountable. Researchers and advocates are shedding light on the disparities and establishing mechanisms to share best practices, to make parents, students and counselors more educated consumers in their college choice and to forge partnerships that span the K-12 to higher ed pipeline.

The Common Core roller coaster. In January 2015, the Chicago public school system announced its intention to ignore a mandate to give all students a new Common Core test known as the PARCC assessment. Pointing to challenges with technology use and questions about the value of the test, school district chief Barbara Byrd-Bennett announced her intention to administer it to a sample of the district, just 10 percent of students. This announcement coincided with Mississippi also pulling out of the PARCC exam.

Just two months later, Chicago Public Schools announced that it would give the PARCC assessment after all. Facing the threat of losing over $1 billion in funding from the state and losing status as a district, the school system backed down and agreed to give the assessment.

Two clear lessons are emerging: States can and will exercise authority in implementation, and districts must choose their battles carefully. Also, the debates over Common Core aren't ending anytime soon and may, in fact, still be gaining momentum. As Common Core becomes increasingly politicized in the build-up to the 2016 elections and as resistance to high-stakes-testing gathers steam, how will large districts like Chicago respond?

Early childhood turning point. Chicago has one of the longest and richest histories of policy, research and practice in support of early childhood education. One of the gold standard and oft-cited programs that delivered impressive results was the Chicago Child-Parent Center model. James Heckman, a University of Chicago professor and Nobel laureate in economics, touts the return on investment of early childhood education. Picking up on Heckman's research, Chicago advocates pushed for a novel idea before the rest of the country caught on: making statewide investments in early learning for infants and toddlers. Now, philanthropists here are experimenting with expansions of preschool programs using social-impact bonds, a so-called "pay for success" financing strategy designed to encourage the private sector to invest in early childhood , assuming those investments will result in savings later in special education and grade retention.

Yet challenges remain. Amid the Illinois budget crisis, preschool enrollment started to slip last year, and the state programs served just 23 percent of eligible preschoolers. With compelling evidence and a track record of success, what else can help make the case? Will a leading state like Illinois push for more access and better quality, or will it rest on its laurels? Does the private sector approach have legs, or will it trigger unintended consequences when it's time to calculate the return on investment?

Choice, redefined. Chicago has been in the thick of the charter school movement, starting with 15 carefully vetted schools in the late 1990s followed by rapid expansion of campuses under existing charters, then another expansion once that cap was lifted, such that today nearly 20 percent of Chicago Public Schools students are now in charter schools. In the Windy City, as in many cities and states, charter performance is mixed, with some dramatically outperforming their neighborhood schools, some lagging behind and many looking about the same.

In Chicago, 12 charter schools are now unionized. It is one of the first systems where the public school system's major union has directed the effort. How will that affect student outcomes? What will the ripple effects be on other aspects of charter autonomy?

In the wake of massive school closings that shuttered 50 schools in 2013, some Chicago residents perceive charters as competitors for neighborhood school resources and are mounting resistance to charter expansion. At last month's school board meeting, a proposal from a traditionally high-performing and well-regarded charter network to move into new space in a North Side neighborhood generated so much opposition from aldermen and other local elected officials that the board stalled their vote for another month.

At the same time, the voices of charter school advocates are still heard on the landscape. Pointing to college acceptance rates and test scores of some charter schools that are seen as high-performing, charter management organizations continue to expand and open new schools.

Given the disagreement about the value and success of charters and the shift toward unionization, it's unclear how well charter school support will be sustained long-term.

Sara Ray Stoelinga is the Sara Liston Spurlark Director and clinical professor at the University of Chicago Urban Education Institute.