Can young children in the United States not identify common fruits and vegetables

Question

On the television show Jame Oliver's Food Revolution there is a memorable scene, when he asks a Grade 1 class (I think) to identify common vegetable, such as potatoes, tomatoes, broccoli and radishes. The children could not identify many of them.

I think the scene was not staged but that it isn't something you would see in the average school. However, my dad thinks it's completely staged.

Was this scene staged and completely untrue?
Is this possible by handpicking a certain school where the producers know the children will how little knowledge of food.
Or is this a more general trend that could be seen in any classroom in the US?

Does anybody have any other information on this particular event, or on the knowledge of school-children in general?

In case anyone is interested, here's the scene I am referring to.

Answer 1

This isn't really an answer, but I thought it was interesting and it's too long to fit in a comment:
(This is more of an answer now; see the edit at the bottom.)

Oddthinking's answer inspired me to do some digging of my own, and I too was met with a lack of immediately relevant academic research. I therefore decided to go about this indirectly by looking at the fruit and vegetable intake of children. This 2009 study by Lorson, Melgar-Quinonez, and Taylor found that 74.1% of children in the US between the ages of 6 and 11 do not meet the recommended daily intake of fruit (on average, these children consume 71.5% of the recommended daily intake). Likewise, among the same group of children, 83.8% did not meet the daily recommended intake of vegetables (on average, consuming 58.3% of the recommended intake). While this study only measured the quantity of intake, I think it is at least plausible to hypothesize that a lack of quantity should be correlated to lack of variety (and thereby lack of familiarity).

Edit:

This 2009 study by Coyle, Potter, Schneider, May, Robin, Seymour, and Debrot surveyed a number of students of different ages in Mississippi, USA, as to their familiarity with different types of fruits and vegetables. The survey asked the students if they were familiar with or had ever eaten 13 common fruits and 7 common vegetables. The 5^th grade students, on average, were familiar with only 85% of the fruits and only 61% of the vegetables. The familiarity did increase slightly with age, with a value of 91% for fruits and 68% for vegetables by grade 10. Therefore, I think it is reasonable to hypothesize that 6 year olds, although not studied, would have had no better (and most likely worse) familiarity than the 5^th graders.

Edit 2:

I need to clarify my summary of the survey method from the second study, as the paper is a little ambiguous. After having re-read the paper, it seems as if the survey listed 13 fruits and 7 vegetables and then asked something like, "List all of the fruits/vegetables you can think of that you have ever eaten, including but not limited to those above." The percentages I quoted are just the number of fruits or vegetables the students listed divided by the number of examples the survey listed. Therefore, if a student received a "score" of 0.77 for fruits, that means that he or she could only recall the names of 0.77*13 = 10 different fruits that he or she had eaten in his or her lifetime. It is therefore possible to have "scores" higher than 1.0. Off the top of my head, I can easily think of at least two dozen different types of fruit that I've eaten throughout my life, which would have given me a score of 24/13 = 1.85.

Answer 2

While researching this, I found a number of people had found the ability of students to identify vegetables question interesting - as they studied whether familiarity with the vegetables made children more likely to eat them. [For example.]

Finding the actual data from peer-reviewed studies was a little harder.

This Master's Thesis showed that preschool students could fairly reliably identify carrots, but that is a common vegetable.

This Honors Thesis showed that common fruit and vegetables where easier than others, for a sample of 40 children around 6 years of age.

When children were asked if they could identify the healthful foods on the cards [...], they were generally better at identifying and classifying more commonly eaten foods such as apples and carrots than less common foods such as Brussels sprouts or exotic foods such as starfruit [...]. Overall, children were able to correctly identify more than half of the fruits (M = 58% ± 11.9) and vegetables (M = 50.03% ± 18.91) on the cards.

I haven't seen the Jamie Oliver show, but with recognition figures of around 50%, I would think there would be plenty of ammunition for an skilled editor to slant the results either way, without needing to stage anything.

Edit: Clarified task performed by eliding extraneous task. These numbers are for identifying the names of vegetables, not for classifying them as fruit versus vegetable (which was also studied, and had higher numbers.)