As of this week, Congress is poised to update the Elementary and Secondary Education Act, the nation’s most comprehensive education law, for the first time since 2001, when it was renewed as No Child Left Behind.

On Wednesday, the House passed its version of the new law, the Student Success Act. The Senate could wrap up debate on its version, the Every Child Achieves Act, by the end of next week.

The road to renewal has been arduous. Just last fall, it was starting to seem like the two chambers might never get to this point. As much as 20% of insiders said that the law, referred to largely by its acronyms ESEA or NCLB, would never be reauthorized. The law expired in 2007, and an attempt by House Republicans to pass a partisan reauthorization bill earlier this year went down as the latest in numerous failed attempts by both parties following last-minute conservative backlash.

While the current process seems like the best shot at reauthorization yet, it isn't without powerful critics. Secretary of Education Arne Duncan said Thursday that, in passing their partisan rewrite, House Republicans “have chosen to take a bad bill and make it even worse.” On Monday, Duncan said that the White House could not support either bill, despite the Senate making a bipartisan effort on its version. But while President Barack Obama has threatened to veto the House bill, he hasn't yet said the same for the Senate's more moderate approach.

To make things more digestible, we've prepared the following primer on what's at stake.

What’s up for a vote?

Elementary and Secondary Education Act (ESEA): Originally signed into law in 1965 by President Lyndon B. Johnson, who aimed to alleviate poverty with educational opportunity. Its previous renewal, the Bush-era No Child Left Behind (NCLB), is widely unpopular for its focus on federally mandated testing and high-stakes accountability measures.

Every Child Achieves Act (ECAA): The Senate's take on the bill, still under debate.

The Student Success Act (SSA): The House bill to reauthorize ESEA, which passed Thursday. Among its more controversial provisions is portability, which would allow federal dollars to follow low-income students to a public or private school of their choice. 

What are the key issues?

Accountability for struggling schools and school vouchers have been the most heated areas of the debate so far. Both bills substantially curtail NCLB-era accountability strictures, which have proved almost universally unpopular and unrealistic. Under the 2001 law, most American schools would currently receive a “failing” designation were it not for the waivers implemented by the Obama administration.

Critics on both the left and right have argued for doing away with many of the federally mandated accountability measures, but Obama and his supporters have defended the need to identify low-performing schools. An amendment to the Senate bill that would have allowed states to opt out of federal accountability entirely was raised Thursday.

"This is unnecessary, misintentioned, won't pass, and undermines the bipartisan agreement that we've reached,” Sen. Alexander Lamar (R-TN), a key architect of the Senate rewrite and chair of the chamber's education committee, reportedly told his party colleagues on the floor prior to a vote on the amendment. It failed, as did a similar proposed amendment to the House bill Wednesday.

The House bill includes a highly disputed “portability” clause, which essentially allows for a federal system of vouchers for low-income students. Democrats have taken a definitively negative stance on that provision, as have many school employee groups such as AASA, which represents superintendents.

Notable changes to the Senate bill that did pass: 

• a Democrat-proposed amendment to make career and technical education a core focus
• a provision that allows teachers to move from state to state without having to redo their certification
• an amendment that requires students with disabilities who use a device to take exams to be familiar with that device before being tested
• an amendment put forward by Sen. Kristen Gillibrand (D-NY) to increase access to STEM for low-income students

(Want a closer look at every amendment to the Every Child Achieves Act? Check out its page here.)

What happens next?

The House process is over for the moment. As for the Senate, no further amendments are scheduled to come to the floor before Monday. Observers say the Senate's debate could wrap up by the end of next week, which would require voting on each proposed amendment and on the final bill.

After that, key representatives from both parties and chambers, will enter the conferencing process, meeting to agree on a compromise reconciling both rewrites. Whatever they come up with will end up on President Barack Obama’s desk to sign or veto.

If he signs the bill, then ESEA will be reauthorized for the first time in over a decade. If not, the two chambers will have to craft and vote on new bills, which would once again open the field for partisan debate.

If and when it passes, the new bill would most notably put an end to the uncertainty of the waiver process for states and is also likely to limit the power of the secretary of education.

How to follow the debate

If you want to get a sense of the ongoing debate, minute by minute, your best bet is Twitter. Check out the #NCLB or #ESEA hashtags to see what lawmakers, journalists, and education policy wonks are saying. If you want to follow the debate in one chamber over the other, just turn their respective bills' acronyms into hashtags: #SSA or #ECAA.

If you’re interested in the status of every single amendment introduced, you can also check out the comprehensive accounting of every action taken on every bill by the Senate or House. Many of the amendments also have hashtags of their own that can be hard to keep track of. Among the higher profile debates are questions of early childhood education funding (#ECE), school choice (#voucher), and charter schools (#charter). Other issues up for debate include support for musical education (#music4core) and school libraries (#libraries).

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