What are the best degrees to become a primary school teacher?
She/he needs to get 5 GCSEs at grades C or above including English and maths (possibly also science in the future). Without English and maths GCSEs you can't teach in the UK, BTECs are no good for teaching qualifications.
She/he then needs to study 3 A Levels to get onto a Primary Education Degree with QTS OR she can study a subject Degree + PGCE of 1 year which is funded to give her a specialism.
If anything goes wrong, as long as she has her maths and English GCSEs there are routes into teaching but it's much harder. She/he had need to wait until she was over 19 and then look at studying an Access to Higher Education Level 3 course in education or similar OR she could study a BTEC in Education or something similar like childcare but she'd need DDP minimum to be accepted onto a teaching Degree.