'Pop goes the Musical' 2012 will see the singers involved in a number of unique curtain calls at London theatres later this year.
Burke will perform in Les Misérables on September 18, Blue will join Jersey Boys on October 11 and Halliwell will be Singin' in the Rain on October 25.
Gray and Stooshe will bring the celebration to a close with separate performances of a Michael Jackson classic in Thriller's November 15 show.
"I have a thing for rain, so I am very excited to be performing in the West End musical Singin' in the Rain and it's all for BBC's Children in Need," Halliwell said. "Just imagine, for one night I get to perform in this classic musical."
Blue added: "We are so excited to join BBC Children in Need 'Pop goes the Musical'. Blue will be turning red for Children in Need when we put on the famous Jersey Boys red jackets for this one-off performance. It is an amazing chance and for such a great cause."
Stooshe commented: "We are so excited to be a part of BBC Children in Need 'Pop goes the Musical'. It will be a totally brand new experience to get up on a West End stage in Thriller, but we can't wait to help such an amazing cause."
Tickets for the special performances are available now at www.lastminute.com/pudsey and include a signed programme, a Pudsey bear, a complementary drink plus access to a VIP after-show reception.
50% of the £80 ticket price will go to some of the 2,600 projects supported by Children in Need that help youngsters facing a range of disadvantages. To find out more visit www.bbc.com/pudsey.
Last year's 'Pop goes the Musical' saw the Sugababes, Peter Andre, Stacey Solomon and Melanie C feature in shows including Mamma Mia and Wicked.