Mr Bolton may claim his 50p (Letters, TES, April 7). Many chickens were hatched by Farmer Patten, and one of them has come home to roost.
The adjectival clause "that were hatched by Farmer Patten's 1993 Education Act" modifies the word "chickens" and therefore the verb has to be plural.
26 Derryvolgie Park
Lisburn, Co Antrim