Final answer:
The sentence 'Some stood on crates to reach their cooking stations' underscores the youth and capability of the junior chefs, demonstrating their resourcefulness without implying it is a hindrance.
Step-by-step explanation:
The effect of including the sentence, "Some stood on crates to reach their cooking stations," is to emphasize how young, yet capable, the contestants are. This detail conveys the youth of the junior chefs, which is in contrast to adults, without suggesting that their youth hinders their ability. It illustrates their determination and resourcefulness in overcoming physical obstacles to participate in cooking at their stations. Therefore, the best description of the effect of this sentence within the context of the paragraph is to emphasize how young, but capable the contestants are.