How many hours is enough?

For parents without access to schooling in the minority language or other intensive forms of input beyond the family, the fundamental challenge—and it’s a challenge that must be addressed day after day, throughout childhood—involves providing sufficient exposure. When a child’s language ability is largely passive, this is generally due to a lack of effective exposure to the target language. (This is often tied to a lack of real need for the language, too, as I explain in the next section.)

But what do we mean by “sufficient” exposure? And what sort of exposure is “effective”?

Sufficient exposure

First, it’s important to again stress that every family is different, with different circumstances and aims, so it isn’t really possible to prescribe a single “magic number” of sufficient exposure for everyone. What’s “sufficient” for one family may not be the same for another. Because of the many variables involved, some families can achieve their aim with less exposure, while other families will require more. Thus, it could be said that every family has its own “magic number” when it comes to the necessary number of weekly hours of exposure to the minority language that will produce the desired result.

The tricky thing is, you can’t actually pinpoint what your own “magic number” is. I mean, in hindsight, once the child is older, it may be possible to look back and make a rough estimate of this exposure. But in the early years—the years when exposure is so vital for fostering active ability in the minority language—you can’t really know.

What should you do?

In my view, even if a clear-cut “magic number” that applies to every family can’t actually exist, this doesn’t mean there isn’t value in estimating a general benchmark of exposure for successful bilingual acquisition in children, based on expert opinion and the wide-ranging experience of others. After all, even if this exposure can’t be precisely quantified, or calculated, shooting for a broad target that has been successful in many cases would surely be more effective than shooting at no target at all.

Again, I want to emphasize that some families may well achieve their own bilingual aims with a lesser amount of language exposure, but I would be cautious about hoping for the same outcome, for your goal, with a similar lower level of input. I suggest that, since you don’t really know your “magic number” early on—how much input you need to provide to foster active ability in the target language—it’s far better to err on the side of greater exposure, which will not only raise the odds of achieving your basic aim, it will enable you to maximize your child’s bilingual development.

In my experience—and others in the field, like researcher Barbara Zurer Pearson of Raising a Bilingual Child, share similar perceptions—a useful target for exposure in the minority language is about 25 hours per week. That’s roughly 30% of the child’s waking hours, depending on routine. Of course, the greater the number of hours, even beyond this, the more you will likely strengthen the odds of success. At the same time, the reverse could also prove true: Less than 20 hours a week might well be a cause for concern if fostering firm, active ability in the minority language is your goal.

Let me be very clear: This figure is simply a broad estimate that can serve as a practical tool for motivating ample exposure to the target language; it is not a “fact” and should not be taken as such. Although the degree of input needed to foster active bilingual ability is a continuing subject of research, I suspect it will always be difficult to draw a hard and universal conclusion about this central issue because, again, there are so many variables involved when considering families across the world.

With that caveat in mind, I feel that making use of a sensible yardstick for regular exposure to the minority language—rather than leaving vague such a crucial aspect of this whole journey—can indeed support the process of nurturing acquisition. I think it’s helpful, as well, to actually count up these hours of input from time to time, and particularly at key stages like the arrival of a new baby and enrollment in a majority language school. This will inevitably be a rough estimate, and that’s fine, but putting this on paper can be eye-opening: It can help reveal whether the exposure you’re providing to your child is generally sufficient or not as well as whether this exposure is as effective as it could be.

Effective exposure

Not only does the exposure need to be “sufficient,” it needs to be “effective.” Plopping your baby down in front of the TV for these weekly 25 hours of exposure to the minority language is unlikely to produce much active ability. TV, as a supplement to other activities, can certainly be a helpful component, but in order to foster active ability, a significant amount of this exposure must be active. In other words, interaction with the language, involving flesh-and-blood human beings, is the key to effective language development.