The mother, who cannot be named for legal reasons, was responsible for one of the biggest single benefit fraud overpayments recorded, according to Department for Work and Pensions (DWP) officials.
She made claims for benefits on the basis that some of her children suffered various disabilities and conditions which affected their care and mobility needs.
But a five-week trial heard that despite the reputed health problems, the children led active lives, taking part in PE classes and other activities, including music, drama and dance, without signs of difficulties.
Some also attended fee-paying schools and performed in professional productions on television and on stage, including in well-known musicals, jurors heard. Prosecutors said that the acting, dancing and singing required for the roles were inconsistent with the care and mobility described in claims for disability living allowance (DLA).
The woman received an overpayment of benefits to which she was not entitled of around £353,000 over an eight-year period from 2002 and at the time of her arrest lived in a seven-bedroom property. The false payments relate to DLA, carer's allowance, tax credits and housing and council tax benefit.
Remanding the mother into custody until sentencing on Friday morning, the judge said she would face a "substantial custodial sentence" as he described her as a "very dishonest woman".
The mother shook her head in the dock as the jury foreman returned overwhelmingly guilty verdicts after the jury had deliberated for just over two days.
The judge told her: "You have been convicted by the unanimous verdicts of the jury on clear evidence of serious offences of dishonesty involving deceiving the public purse and the taxpayer of around £350,000 over a period of some 10 years."