I'm sure I've also heard a Brass Ensemble at concerts, the Jazz Ensemble was playing (very nicely) at the Carol Service / Concert last week, and Downfielders Barn Dance Band would happily have a Euph (though be warned, your daughter would not get to do paid for gigs 'till Y9). There's also a Wind Band. If she's > grade 5, then she could join Senior Orchestra that starts in September, otherwise she'd have to wait until Feb to join Junior Orchestra; the orchestras are age and grade differentiated, so Y10 up can only be in Senior Orch, Grade 5 or over can be in either irrespective of age, and Years 7 to 9 below grade 5 can only be in junior. Senior Orchestra & Downfielders are all mixed-gender with boys from Marling.
About the only things she wouldn't be able to join would be Junior / Senior Strings or the woodwind ensemble.
In common with all the grammars and most of the non-grammars, there are a fair few from SHS who play in Gloucestershire Youth Orchestra, Glos Youth Wind Orchestra, Glos Youth Jazz Orchestra and Youth Choir. Just getting ready to drive to Chelt Town Hall to see the GYO & GYWO Xmas Concert (narrator - Keith Allen (aka Lilly's dad)) this evening, complete with the second performance of 'Journey' - last performed at the Royal Albert Hall a month ago (err - and last rehearsed then as well) ... Should be fun.