Are you in France and she is still in maternelle? If so, DC learnt to read and write in CP ie the year after the final year of maternelle, and learned really, really quickly - beautiful handwriting and reading to a pretty high standard by the end of the year. DC found it really frustrating in maternelle, they used to come out saying that they had spent the day at the factory putting yellow blocks in yellow piles and red blocks in red piles - such a contrast to what they learn the next year.
I would keep your dc reading bits of the Chip and Biff books every night while in CP and beyond - we know a lot of English kids whose reading and writing in English is behind because they only focused on French. It is those who continue to read and write in English at home and whose grammar and spelling is corrected and who parents are engaged with it all who do well at both languages.
Proper English grammar isn't always taught in the schools, it depends on who is teaching - the native French who are teaching English are usually better, as the English English teaches tend to teach TEFL which is a bonkers mix of progressive and linguistic grammar. In France formal grammar is taught and if you were taught proper English grammar then most of it is easy to understand and translate. DC has learnt a fair bit of English grammar while doing the French grammar. We have learned French and the equivalent English tenses at the same time too - good for making sure that DC says "would have" not "would of"!
I think it is worth learning to write in the copperplate script like the other children (if this is France), as it is really good for fine motor skills. Easy to adapt and change later on if your DC wants
The older Oxford Tree books are fantastic for learning English grammar and spelling - not so sure about the more recent ones - I have got the impression that more recent things go down the progressive route but I might be wrong there.
Apparently the UK is the only developed country in which 55 - 65 year olds have higher levels of literacy than school leavers - thanks to our 50 years of increasingly "progressive" grammar teaching.