Reading with young children is among the most consistently recommended activities in early childhood, and the recommendation is well supported.
What's less widely known is that how it's done affects the outcome considerably, and that a specific approach has been repeatedly shown to produce larger effects.
The evidence base
Associations between shared book reading and language development, vocabulary and later literacy have been found consistently across many studies.
Intervention trials — teaching parents specific reading techniques and measuring child outcomes — have found effects on expressive language in particular.
The mechanism is reasonably clear. Books contain vocabulary and sentence structures that don't appear in everyday conversation. Exposure to that language, in a context with a supportive adult, builds vocabulary and comprehension.
Dialogic reading
The specific approach with the strongest support, and it's quite different from reading a book aloud.
The principle is that the child becomes the storyteller and the adult becomes the listener and prompter. Rather than reading the text while the child listens, you ask questions, follow their interest, and expand on what they say.
A commonly taught structure involves prompting the child to say something about the book, evaluating their response, expanding on it by adding information, and repeating the expanded version.
In practice this looks like pointing at a picture and asking what's happening, listening to a two-word answer, and saying it back as a fuller sentence with something added.
Trials of this approach have found larger effects on expressive language than reading conventionally, which suggests the interaction rather than the text is doing much of the work.
What matters practically
Talking about the book more than reading it. Particularly with younger children. Getting through the text is not the objective.
Following their attention. If they want to look at one page for five minutes, that's fine. If they want to skip, skip.
Repetition. Children want the same book many times and this is developmentally useful — repeated exposure is how vocabulary consolidates. The tedium is entirely one-sided.
Vocabulary beyond their level. Books introduce words that don't come up in conversation. Explaining unfamiliar words as they arise is where a substantial part of the vocabulary benefit comes from.
Making it enjoyable. Enthusiasm, voices, expression. Engagement is the mechanism and a joyless session delivers less.
Print versus screen
An area with genuine research and a nuanced answer.
Studies comparing shared reading of print books with electronic books have generally found more parent-child conversation and better comprehension with print, particularly where the electronic version contains interactive features.
The proposed explanation is that interactive elements — sounds, animations, games — distract from the narrative and from the conversation, and shift the interaction from talking about the story to operating the device.
Simple electronic books without interactive distractions appear to perform closer to print.
Audiobooks are a different case and have their own value, particularly for older children, though they don't provide the shared interaction that produces much of the benefit in early years.
The socioeconomic dimension
Worth addressing because it shapes a lot of the research and a lot of the policy.
Differences in early language exposure between children from different backgrounds have been extensively documented, though the magnitude and interpretation of some influential early findings have been questioned in subsequent work.
What's less contested is that access to books varies, and that book access is a modifiable factor. Programmes distributing books to families have shown effects on reading frequency.
Libraries matter enormously here and are frequently undervalued. Free access to a large and rotating collection removes both the cost barrier and the repetition problem.
Practical notes
Frequency over duration. Ten minutes daily is better than an hour on Sunday. Consistency builds the habit and the habit is what persists.
Let them choose. Autonomy increases engagement, and a book they chose gets more attention than one you did.
It doesn't have to be at bedtime. Bedtime is convenient and it also means reading happens when everyone is tired. Other times work.
Non-fiction counts. Books about vehicles, animals or how things work contain vocabulary storybooks don't, and many children prefer them.
In whatever language you speak best. Reading in a home language rather than a second language you're less fluent in produces richer interaction, and there's no evidence this disadvantages later learning of an additional language. The opposite, if anything — strong first language skills support second language acquisition.
Older children
Reading aloud is frequently abandoned once a child can read independently, and there's an argument for continuing.
Children's listening comprehension exceeds their reading comprehension for several years, which means read-aloud books can be more complex than what they can read alone, exposing them to richer language.
It's also, for many families, one of the few remaining shared activities as children get older, which is worth something independent of any measurable outcome.