I myself read the full novel
Flowers for Algernon in first or second grade, and oh yes, it moved me to tears of both wonder and joy. I learned immense lessons about compassion, humility, and living the best you can while you can. I -needed- those messages, and I should hope someone nearing 8th grade is more than ready for what treasures this book has to offer, in either full or shortened form.
As to the ‘sexuality’ objections, they didn’t bother me at that age or any other - they made the protagonist more human, and once he has a true intellect and sense of social morality, he deals with it appropriately too, rather than sliding into over-scrupulosity and fear, he understands that such is how the body functions. And if your daughter is in late 7th or about to start 8th grade, chances are she’s had some experience with her own ‘nocturnal emissions’ as well (yes, females have them too) since menarche is very likely any time now!
Eheh, sorry to be the bearer of a little traumatic news there, perhaps, but it deals with the flesh as it is, natural and no sin.
It is a beautiful and heartbreaking read, as well as groundbreaking. At that age, don’t discourage discovery, please! Now is the very best time of all to read and learn and grow, though all times are wonderful.