 Fifteen children who are between ten and twelve years old are chosen for each filming, along with one alternate.The mandatory waiting period after taking the online contestant exam is one year, although this may be adjusted by the show's production team based on the test schedule.Prospective contestants who have completed an in-person test and interview remain in the contestant pool for 18 months, only after the expiration of which may they take the online test again and attend another in-person audition.