The development of Scratch 2.0 was a process taking several years and many stages, leading to a release on May 9, 2013. Though released, it is still constantly being updated with new features and bug fixes. You can see many versions of Scratch 2.0 here.
The announcement for Scratch 2.0 came in January 2010, thanks to andresmh, though Scratchers were not allowed to view Scratch 2.0 till in August of the same year. During that time, the Experimental Viewer went public for several months, as pictured to the left. The viewer was an online editor meant to experiment with Scratch, though it lacked several simple features, like costume editing, comments, and many more. A Scratch 2.0 Transition Team was formed to help Scratchers transition from Scratch 1.4 to 2.0.
Meanwhile, in February 2011, the Flash Player entered the Scratch website, though the Project Editor did not come in Flash yet. The Flash Player was and is a way to view projects online, while carrying the benefits of faster projects, causing many Scratchers to applaud it. As time passed, the project viewer received many updates, and later became the official project viewer on May 9, 2013.
The first known version of the project editor followed in Scratch Day of May 2011, during which a limited audience was allowed to view it at MIT. A little afterwards, the ST also started releasing progress reports on Scratch 2.0.
On February 16, 2012, Scratch entered alpha development. The next taste the public got of Scratch 2.0 came a long time later, though, on Scratch Day 2012. During that time, the alpha site for Scratch 2.0 (at alpha.scratch.mit.edu) was released for a few days, and a preview video of Scratch's new features was released here. After the event, alpha testers were brought in to test the site. These alpha testers were notified by the Scratch Team, and given a code to allow them to access the beta.  Of the testers there were:
- Community moderators
- Selected educators
- Collab counselors
- Former curators
- Scratch Design Studio curators
- TBG moderators
Along with that, 500 additional testers were later brought in to test the website. To have become an alpha tester, a Scratcher must've posted on this project by Lightnin, and then the first 500 requests were accepted. Some users, though, were able to use a loop-hole in the website to preview the alpha website. It was encouraged that these people acted as if they did not use the loop-hole.
The beta development of Scratch officially began in December 2012, though public Beta testing began on January 28, 2013. The Scratch Team had migrated all current user accounts and projects to the beta website, at beta.scratch.mit.edu, in preparation for this date. Once the beta website became public, beta testers, as they are commonly referred to, could look at and test the website while it was in development. Profiles created after December 2012, though, could not test the website due to the fact that their accounts weren't migrated over. This was a commonly asked topic by New Scratchers after the start of the Beta.
The Beta website finally went down on May 6, 2013, to later replace the main Scratch homepage.
- See also: Category:Scratch 2.0 Images
The Front Page of the website prototype.
A Scratch 2.0 search mockup by Gaia (Scratch Team member).
An example project showcasing the new video blocks.
A procedure and its usage, in the Scratch Day 2011 pre-alpha.