A productive day of bargaining between leaders of the Denver school district and its teachers union stretched into Thursday morning as the two sides met separately to work toward a deal.

That deal got struck just after 6 a.m. Thursday, more than 20 hours since the bargaining session began and just before the fourth school day of a teacher strike would have begun. Here’s our story about the deal.

As we did Tuesday, our team spent Day 3 of the strike — and the entire night — tracking developments across the city. You can catch up on the highlights here, including scenes from picket lines, a detour for some cute dog pictures, and details from bargaining.

6:30 a.m. That’s a wrap, except for preschool families

We’ve just posted a story about the deal, so tune in there for details. We’ll have more throughout the day on what the agreement means for teachers, students, schools, and the education policy world.

For now, the day is beginning with praise for the Denver district and its teachers union for toughing out talks — here’s a tweet from Gov. Jared Polis — and questions among educators and families about what’s supposed to happen in schools today.

Here’s the official word from Denver Public Schools:

What’s your school like today? Let us know. And if you’re among the readers who appreciate Melanie for her bargaining all-nighter and the entire team for its tireless strike coverage, you can always donate to Chalkbeat. Thanks for joining us on this journey!

6:12 a.m. Dawn breaks with a deal

This is what you need to know about Denver’s response to the teachers union’s latest proposal:

Followed shortly by this:

It’s a Valentine’s Day love-fest! One clear highlight: Teachers will continue to get bonuses for teaching at high-poverty schools. We’ll have all the details about the deal shortly.

We’re also playing fast and loose with definitions of time right now. The official sunrise today in Denver is 6:54 a.m. Schools start opening a little bit after that. A big question today will be what happens inside them.

5:30 a.m. Back at the table

Union negotiators are back at the bargaining table after a late-night break, more than 19 hours after this session first started. Rob Gould says the union has a new proposal: “We think it may end the strike.”

2 a.m. Thursday Into the wee hours of the morning

It’s now been about six hours since the two sides last appeared together at the bargaining table.

We still don’t have a clear answer to the very practical question on so many people’s minds: If a deal is reached after all these hours, are striking teachers returning to work Thursday, or will they be out at least another day?

We heard from one school-level union organizer who told us Wednesday night that teachers should prepare to strike again until they hear otherwise, that a tentative deal should include a return-to-work date, and that union members do not need to vote to vote to ratify a deal before returning to classrooms.

We’ll keep you posted.

11:35 p.m. When is the tipping point?

Both sides continue to work separately on their proposals. It’s not clear how much longer they’ll work, but if they weren’t hoping to reach a deal before dawn, presumably they would have wrapped up for the night with a plan to meet tomorrow.

One of the outstanding questions is whether teachers will go back to work tomorrow, if a deal is reached tonight. The later we go the less likely that seems.

9:12 p.m. No, we haven’t forgotten about you

The district came back briefly a while ago to agree to some aspects of the union salary schedule, but since then, the two sides have been in caucus, crunching numbers. The optimists have lost the Chalkbeat Colorado office pool about what time we would see a deal.

7:11 p.m. Getting closer

That was fast. After a short caucus, the union came back to the table and gave a lightning-fast presentation on its new proposal — which moved the two sides closer.

The union accepted the district’s proposed salary schedule of 20 “steps” and seven “lanes” separated by increments of 18 college credits (or equivalent training courses).

“We see how far you all have moved,” lead union negotiator Rob Gould said, “and in an effort to get a deal tonight, we’re accepting your number of lanes and your steps.”

The union also accepted the district’s proposal to cap the number of “professional development units,” or training courses, teachers can do at two per year. It had previously proposed a cap of three. The number matters because teachers can use those courses to change lanes and get raises.

There are still several areas of disagreement, including the size of the bonuses and incentives for teachers who work in high-poverty schools and hard-to-fill positions.

The district is now reviewing the union’s proposal.

5:40 p.m. ‘This is big’: The district offers a new proposal, and one big sticking point remains

The negotiators are back — and the district has a new proposal that more closely matches what the union has been asking for.

The changes involve both the “steps” and the “lanes” in the salary schedule. The district’s new proposal has 20 steps, which is the number the union has been pushing for. (The district had been holding firm at 30.) The lanes have shifted in the district’s proposal as well, requiring teachers to earn fewer credits to jump a lane and increase their pay.

The district also offered a compromise on the “longevity” raise for educators with 10 years of service in the district. It has to do with educators who wouldn’t be able to cash in their longevity because they’re already at the highest lanes.

But the two sides have not come to an agreement on a crucial point: retention bonuses for teachers in the district’s 30 “highest-priority” schools. The district’s proposal keeps those at $3,000.

The union is going to meet to discuss the new proposal. But the mood remains positive, with teachers clapping, Melanie reports. “This is big,” Gould said.

One reason the union has pushed to end the retention incentive is because it believes putting that money into base pay will do more to keep teachers.

But if the district is offering a salary schedule the union can live with, along with the highest-priority incentive, members might not mind keeping the incentive after all.

“The district has absolutely met us their halfway,” said Rachel Sandoval, a teacher at Godsman Elementary School in southwest Denver, who has followed the negotiations closely. “We’re going to have to meet them at some point.”

3:58 p.m. What teachers say about the issue on the table right now

In the library basement, the mediator has just let observers know that the union and district are each meeting to discuss contract terms right now. The official word: “I have the parties upstairs working really really hard on some things.”

While we wait for them to return, take a look at our newest story, about what teachers across the district say about the bonuses and incentives that make up the biggest remaining sticking points.

“I’ve never worked anywhere where they couldn’t tell me how much I’m making,” one teacher told us about the bonuses she has received for working at a high-poverty school. “It was weird to me.” The story features 10 teachers’ perspectives.

3:18 p.m. Attendance is holding steady

This just in from Denver Public Schools:

Those numbers are very similar to what the district shared on Monday, suggesting that families and teachers haven’t wavered since the strike’s first day. But there’s a big asterisk: “This is a joke,” one educator tweeted in response. “I know this is an average but student attendance is way below 75% at the school I work at. Yesterday it was 50% at best.”

2:56 p.m. A first-person perspective

A core issue in the Denver teachers strike is that the district’s salary-and-bonus system has left many teachers with inconsistent pay and less ability to plan for the future.

We just published a First Person essay from one of those teachers, Charlie Gaare, who says she changed her plans for growing her family because of how she’s paid. Check it out here.

2:08 p.m. Canines for K-12

Today is heavy on policy details and if you’re like us, you might need to rest your brain while the district and union pause their negotiations. We’ve got the right content for you: a roundup of the dogs of the Denver teacher strike. See the whole thing here.

1:55 p.m. “We know it’s important to you”

This afternoon’s negotiations are filled with signs that the Denver teachers union is eager to reach a deal with the district over teacher compensation. Here’s the latest from Melanie:

In the past 50 minutes, it feels as though the district and the union have moved closer than ever. The union accepted much of the district’s proposed language around how teachers complete “professional development units.” The union also agreed to the district’s idea of giving teachers a raise for 10 years of service.

Even more significant: Union negotiators said they’d be open to the idea of providing incentives to teachers who work in “highest-priority” schools. The district wants to give teachers who return to those schools year after year a $3,000 retention bonus. Up until today, the union had rejected that idea. Instead, it wanted to use that money to increase the salaries of all teachers.

“We are open to the incentive because we know it’s important to you,” lead union negotiator Rob Gould said. “And we’re willing to entertain your ideas if we can get the base salary schedule that our teachers need.”

The two sides are now caucusing, or holding internal discussions.

1:33 p.m. Mixed results for “highest-priority” incentives

The Denver district says giving teachers at certain schools more money is essential to ensuring that they are staffed with strong teachers. But the incentives that have been in place since 2015 — and that are being discussed at the bargaining table right now — haven’t made that happen. From our story last week:

The district began offering an incentive to teachers at 30 “highest-priority schools” in 2015. These schools have high rates of students living in poverty, students who switch schools from year to year, special education students, and English language learners.

At nine of the 28 schools that have consistently received the incentive, teacher retention has been higher each year than it was in 2015.

But at six schools, retention has been lower each year than it was in 2015. At the remaining 13 schools, retention has gone up and down during that time period.

One thing district and union officials are coming to terms on right away: not calling the schools “hard-to-serve,” a common shorthand for schools that have many needy students and high teacher turnover. After union negotiators criticized the term, interim Denver schools chief Susana Cordova said she agreed. “It is offensive to start from a deficit approach,” she said.

1:19 p.m. It’s happening

For the first time since the strike started, negotiations have turned to pay incentives for teachers at the Denver district’s “highest-priority” schools. The district wants to give teachers at those schools an extra $3,000 a year, but the union wants the bonuses eliminated entirely in favor of increasing base pay for all district teachers.

This is among the final remaining details standing between negotiators and a deal, but it’s a big one — and it stands for in a longtime ideological debate in the education world.

1:15 p.m. A buoyant post-lunch mood

District and union officials are back at the negotiating table after a break to caucus (the union) and have lunch (both sides). The union’s lead negotiator, Rob Gould, got a rock star’s reception from the observers, who are almost all district teachers on strike, according to Melanie. Cordova and an audience member cracked jokes with each other. And there’s also news:

Many had hoped the strike would end after today, and Gould seems determined to reach a deal with the district, saying that he’s not prepared for another night with little sleep.

11:48 a.m. Energy on the picket line, and excitement about a possible resolution

Our reporting team is getting the message loud and clear from teachers on the picket lines today: They’re committed to the fight but excited for the strike to end. See this video of North High School English teacher Megan Ross that Eric filmed for an example:

The mood appeared similar at Trevista at Horace Mann, one of 30 “highest priority” schools where teachers get pay incentives the union wants to eliminate. Teachers at highest-priority schools joined the strike at a slightly lower rate on Monday. Second-grade teacher Emily Kil told Eric that she and her colleagues are as committed to the strike as they were on Monday.

“It is hard on Day 3. You’re a little more physically tired,” Kil said. “But mentally we’re still in the fight and we’re hoping that it’s going to end today.

11:15 a.m. So about those incentives …

While the union caucuses, or meets in private, to discuss the district’s offer, we’ll take the opportunity to note again that some issues that had seemed like major sticking points haven’t come up this week. Those are the size of bonuses for teachers at high-poverty schools, and whether teachers who return year over year to 30 schools designated as “highest-priority” should get any extra pay at all.

Are union and district officials getting easy disagreements out of the way first and saving the tough stuff for last? If that’s the case, it’s hard to imagine the strike ending quickly.

Or are these incentives not actually that contentious? That would be surprising, given how union and district officials have talked about them in the past. At some point in the not-too-distant future, we’ll know the answer to these questions — and how much teachers in these categories of schools will be paid under ProComp going forward.

10:55 a.m. Claps and snaps as negotiations open

Negotiations are underway. Here’s an early dispatch from Melanie:

First up today: The district brought a new proposal that elicited clapping and snaps of approval from some teachers in the audience. The biggest hit? That the 45 hours required to complete a “professional development unit” — training courses that can be cashed in for raises — could include time during or outside the school day. The union is caucusing to consider the proposal.

Want to hear what satisfied union supporters sound like? Check out this video posted by a local TV reporter:

10:44 a.m. A cake for Cordova

A few union supporters showed up to negotiations this morning bearing a supermarket sheet cake iced with a message for Denver Superintendent Susana Cordova: “You can eat it too!”

The cake is a reference not to Marie Antoinette and class warfare but to an exchange Cordova had with lead union negotiator Rob Gould Tuesday night.

As the two sparred over whether teachers should be allowed to complete training courses during school hours, Gould asked, “You’re saying that we can’t have our cake and eat it too?” Cordova responded: “I thought we were in the business of creating a new recipe for a different cake.”

10:37 a.m. Your morning teacher strike earworm

Here’s another snippet from this morning’s pickets: a video of spirited teachers gathered across the street from North High School. We challenge you not to get the Twisted Sister cover stuck in your head.

10:35 a.m. A parent’s view

Just a reminder that schools are operating with threadbare staffs and offering instruction that’s limited at best. The union says the situation underscores how essential teachers are, while the district is focused on maintaining stability and security for students. The dynamic has left students and their families making tough decisions about whether to attend.

“My Junior just left school to ‘do real work’ (ie study AP History) because the sub handed them worksheets,” Aimee Giese tweeted this morning. “My son is also negativ[ely] affected by because the media rooms are closed so he can’t work on his AP Art projects (which by the way, is where he’s applying for college).”

10:08 a.m. A compromise

As Melanie waits for bargaining to start, here’s a reminder of one area where the union has ceded some ground: around the extra training hours required for teachers who want to move “lanes” and increase their pay. When talks opened on Tuesday, the district wanted all of the hours to happen outside of the regular workday, and the union wanted teachers to be able to complete “all or part” of those hours while they’re already at school. Last night union negotiators compromised to “part.”

10 a.m. Back in the basement with Rocky

Negotiations are supposed to open any minute. Melanie Asmar will share up updates from the basement of the library. Here are the first two: First, the crowd of union supporters has been joined by a scaly ally: Rocky, a class lizard who accompanied a teacher to today’s negotiating session.

Plus, Melanie reports that Tuesday’s burrito and pizza odors have been replaced by the smell of hot coffee — a necessity after last night’s talks ended just 10 hours ago.

9:15 a.m. A sunny day on the picket line

If there were any fears that energy might flag among striking teachers, this morning’s picket lines should put them to rest. We’re seeing social media posts from across the city featuring red-shirted educators and their allies with megaphones, signs, and songs. Here’s one example, filmed by a teacher outside Greenwood Elementary School:

Want us to see your pictures? Tag @ChalkbeatCO when you post them!

8:30 a.m. No official attendance or participation data yet

How many teachers joined picket lines on Tuesday? How many students made it to school? There’s no official data yet, though the word from the district is that conditions on Day 2 were “about the same as Day 1.” (As a reminder, just over half of teachers participated in the strike’s first day, according to the district, and three-quarters of students attended school.) The numbers matter because they’re a useful barometer of how much stamina the union has and how confident members of the public remain about safety at schools.

8:15 a.m. Checking in on immigrant teachers

Remember how Denver Public Schools warned schools that it would report teachers who joined the strike to immigration authorities? The district apologized and said the warning was an error, but our reporters found that the episode is still having an effect on at least some of the 128 teachers whose visas are dependent on their employment.

Here’s what an teacher from Venezuela told us on Tuesday: “I would prefer to be outside [picketing]. … I want to make my voice heard. But it’s scary. I don’t know what could happen, and it’s my family that is at risk.” Read the whole story here.