The 6K practice room for the 2027 season: now in the browser too

“Wir lassen dich nicht allein”: that is the motto under which 6K UNITED! will once again bring more than 100,000 children onto the big arena stages in June and July 2027. Seven cities are on the plan this time: Düsseldorf, Hamburg, Mannheim, Berlin, Hanover, Munich and, for the first time, Vienna. Until then, the participating schools and choirs have a whole school year of rehearsal work ahead of them, and that is exactly what the 6K practice room in cori is there for.

We started out with 6K UNITED! as a partner at the end of the 2026 season (here's how that came about). Since then, thousands of children have practised their 6K songs with cori, and their feedback, that of their teachers and that of 6K have shaped the practice room for 2027. This post sums up what's new and how you get into the season.

What the 6K practice room is

In short: the official practice area for everyone singing with 6K UNITED!. Children get an access code from their teacher, enter it and land in a closed area in the 6K design. Inside it are all the songs of the season as practice videos, the warm-ups to get voices going and the appointments of their own group. No account, no email address, no ads, and free for every participant.

More about the thinking behind it is on the 6K UNITED! x cori page. This post is about what has been added since the launch.

New: the 6K practice room in the browser

The most frequent piece of feedback from last season wasn't a feature request but a question of place: "And how do I show this in the music room?" There's no phone hanging on the whiteboard, no app can be installed on the school PC, and not every family has a tablet a child is allowed to practise on.

That's why the 6K practice room is now in the browser as well. The address can be written on the board: cori.music/6k-proberaum, then click Practise in the browser, enter the access code, done. It's the same practice room with the same songs, videos, follow-along lyrics, sheet music and appointments, with the same code as in the app. The browser remembers that you've joined; next time you open it, you carry straight on.

A few things remain deliberately reserved for the app, because they need the microphone or the device's storage: the sing-along with live pitch feedback, the streak and practising without an internet connection. For lessons at the whiteboard and practising on the school PC, the browser is entirely enough; for practising with feedback at home, the app is worth it. Exactly what works where is in the help article Opening the 6K practice room in the browser.

New: groups and appointments for teachers

In the first season, the 6K practice room was purely a place for children to practise. Teachers quickly told us what they were missing: a place where their class comes together. So now there are groups.

With the teacher key from 6K UNITED!, a teacher creates a group, usually one per class or choir. The children join it by name, with no second code. From then on the group has a calendar of its own: the teacher enters the weekly rehearsal, the performance at the school fete and the bus trip to the arena, the children accept or decline, and the teacher sees in advance how many to expect. That works the same way in the app and in the browser.

What there still isn't: chat, comments or any form of social feature between children. Only the teacher sees a group's name list. The guide to it: Creating and managing 6K groups.

New: follow-along lyrics and sheet music right next to the video

The practice videos with chapter markers were already there in the first season: a tap on warm-up, choreo, left or right jumps exactly to that spot instead of spooling. What's new is what happens beside it.

The follow-along lyrics now scroll in sync with the video and highlight the line that is currently being sung. For children who don't yet know the words securely, that is the difference between singing along and listening. And where there is sheet music for a song, it sits as a PDF right next to the video, one tap away, instead of in a folder you have to go looking for first.

What has stayed the same

Everything that has defined the 6K practice room from the start still applies, and we checked every new feature against it as we built:

• No accounts for children. The access code and a first name are enough, in the app as well as the browser.
• The voice stays on the device. The sing-along analyses pitch directly on the device. Children's recordings are never uploaded to our servers.
• A closed space. No ads, no public profiles, no social features. Only those with a code get in.
• Servers in Germany. GDPR-compliant, with data minimisation as the default.

How to start the season

If the 6K access code is already in your inbox:

1. Get the app or open the browser. cori is free on the App Store and Google Play, or you open cori.music/6k-proberaum and click Practise in the browser.

   

2. Enter the code. Teachers take the teacher key and create their group. Children take the general code and look for the group by name.

3. Pass the code on. Onto the board, into the letter to parents, into the class group chat. Parents install the app on the family device or open the browser, enter the code, and the child can practise.

The step-by-step guides are in the help centre: Joining with the 6K access code, Songs, videos and sheet music in the 6K practice room and Appointments in the 6K practice room.

For every other choir

The 6K practice room is the biggest project cori carries so far, but the observation behind it holds for every choir: the time between rehearsals decides whether a piece sticks. If you lead a youth or adult ensemble and know exactly that problem, the cori feature overview is the right place to start. The same building blocks, without the child-specific trappings.

Questions about the partnership, about setting things up in your school or about cori in general can go to info@getcori.app. We usually reply within one working day.

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More about this: 6K UNITED! x cori | How the partnership came about | About 6K UNITED!