Waiting for Approval
Once you have sent the application for Change of Status to USCIS and your record has been added to the SEVIS database, you have gained the right to remain legally in the United States until your application is either approved or denied. While your application is pending you should remain in the U.S. Currently it takes USCIS 2 to 4 months to reply to student visa candidates depending on the USCIS center processing the application.
If your spouse or children are visiting the United States with you as your dependents, they can apply for F-2 Family of Foreign Student status when you apply to change your status to F-1. They will be included on your form I-20 by the DSO and will be added to the SEVIS database. At the time of application for change of status, you will have to prove the availability of additional funds to cover their living expenses and also prove your relationship by providing the original translation of your marriage and/or children's birth certificate. Their F-2 status will be dependent upon your status as an F-1 foreign student. This means that if you change your status, your family must change their status, and if you lose your status, your family will also lose their status.
You may be advised to extend your current visa before applying for a change of status, depending on the duration of your current visa. Discuss your situation with the Admissions Department of the school you are planning to attend and alert them to the fact that you are nearing your visa expiration date.