The spread of ability in a primary English class is wider than in any other subject. Some children have had extra lessons since kindergarten, while others met the alphabet properly for the first time in Grade 1. Aim your teaching squarely at the middle and you miss both wings: the front of the room gets bored and starts causing trouble, and the back can't keep up and switches off. The goal isn't to teach everyone the same thing. It's to give each child work that stretches them by exactly the right amount.
Tasks in three layers: one floor, different ceilings
Build every activity in three stacked layers. There is a base task everyone has to reach, such as matching eight words to pictures. There is an extension for the fast finishers, such as writing three sentences using those words. And there is an open challenge with no fixed end, such as making up a short story that uses all of them. Everyone starts from the same place, so no child is publicly labelled as one of the weak ones, but the ceiling stays open for anyone who can climb.
Worksheets that come as levels 1, 2 and 3 on a single topic are the ready made version of this. The whole class studies one topic, but the sheet in each child's hands is pitched at their own difficulty.
The buddy system: turn the gap into a resource
Pair a strong child with one who's still catching up, and give both roles some dignity: one is the captain, the other is the pilot. The captain helps when the pilot asks and never takes over the controls. The peer tutoring research all points the same way. The person who gains most is the strong child doing the teaching, because explaining something until another person understands it is the deepest kind of learning there is. Meanwhile the child catching up gets a private tutor who speaks their language.
Swap the pairs every month, so nobody gets bored and no pairing hardens into a permanent clique.
The one thing never to do
Never sort the class into permanent ability groups that everyone can see. The top group and the bottom group are labels a child carries for the whole year. A child placed in the bottom group in term one stops trying, because they believe their position has already been decided. Keep the level in the work they're holding, which can change every week, rather than in the child, where it follows them all the way to secondary school.