This weekend the The 24 Hour Plays – Old Vic New Voices returns for a sixth year, with 50 actors, directors, writers and producers between the ages of 18 and 25 coming together to create seven short plays in just 24 hours, all of them performed before an audience of 1,000 on the history-soaked stage of the Old Vic.

Following an initial get-together on Saturday evening, during which the writers get a feel for the actors and directors who will be bringing their work to the stage, the whole night is spent writing. Early on Sunday morning the scripts are handed in, are read by the directors and pitched to the producers, and casting decisions are made. During the day, the plays are rehearsed while producers source props and costumes and preparations are made for the performance that evening.

It is an extraordinary process to be part of for all of the participants, but for the young writers involved, the experience is a particularly intense one: rather than sitting at home alone, crafting a piece of work over many months, the writers must be immediately responsive to the other participants and produce a stageable play in just one night. Rather than sending a script to agents, theatre literary departments and playwriting competitions, then waiting months for feedback, they see their work being performed on one of London's most illustrious stages just 12 hours after putting the finishing touches to it.

Morgan Lloyd Malcolm took part in the first 24 Hour Plays for emerging artists back in 2005 and has since gone on to be commissioned and produced by Hampstead Theatre (the play in question, Belongings, has just earned her a nomination for the Evening Standard's Most Promising Playwright Award) and the Lyric Hammersmith (last year's Dick Whittington and this year's Aladdin), and win a Fringe First (You Once Said Yes, co-written with Katie Lyons). She looks back on the experience as a fundamental one in her development as a writer, explaining that not only did the project introduce her to a number of very talented theatre-makers with whom she has gone on to collaborate, it also boosted her confidence and set her on the road to finding her own voice after years writing as part of a team.

24 Hour Plays is unique in its scale and particulars, but there are other projects around that offer comparable benefits to writers even if they don't have the cachet of working at the Old Vic.

Next Best Page is an intriguing example. The project launched in January, inviting writers to submit the first page of a script. The page selected was made available to download and, week by week, writers have been invited to submit further pages to continue the drama. Meanwhile, readings have taken place at regular intervals to make sure the play has been progressing in a stageable direction. Forty-six pages of what will be a 52-page script have been completed (if you're interested in contributing, the deadline for page 47 is Saturday night at midnight), and over 1000 people have submitted pages to the project so far. The play, Power Lines, will be produced at Theatre503 at some point in the new year and the possibility of a UK tour has been mooted.

Next Best Page is an undeniably contrived way of writing a play, and the success of the piece as a complete work is far from guaranteed (collaborative writing projects are difficult to pull off even in the most favourable of circumstances – look what happened with the National Theatre's Greenland earlier this year), but the project is an unusual and exciting way of getting people writing for theatre. The producers report having received lots of really positive feedback from participants, many of whom say that taking part has inspired them to pursue other writing opportunities. As with The 24 Hour Plays, there in an immediacy to the process that incentivises it – these writers aren't exactly seeing their work performed immediately, but they can watch the piece develop every week and if they are unsuccessful with a submission can try again and again until they get a page selected. They also get the sense of being part of something, itself a major confidence-booster that facilitates the writing process.

There's no magic formula for forging a successful career as a playwright: it takes talent, inspiration, confidence, perseverance, pragmatism and not a little luck. Projects such as The 24 Hour Plays and Next Best Page offer no guarantees, but by turning the writing process into a time-trial challenge, a collaborative game, a creative adventure, they have the potential to guide their participants to different ways of writing and thinking about their work. It worked for Morgan Lloyd Malcolm, Mike Bartlett and plenty of other 24 Hour Plays alumni and will surely work for some of this year's crop too.

On your marks, get set, write!