Scott and Turner's was some kind of brand of syrup or something, to be dribbled over anything you wanted to be sweet and syrup-covered. The headline in this 1948 ad reads "Here's the vitamin C and sugar they need". Say what? Yep.
It sounds really weird to a modern person, for whom getting enough calories is not a problem. High calorie, low nutrient food is cheap and plentiful now, but in 1948 London, it wasn't to easy.
Actually, sugar (well, a form of it) is absolutely vital to sustain human life. Glucose is the only energy source used by the brain, and horrible things like diabetes are what can happen when a person's body doesn't deal with sugar properly. However, your body can make glucose from almost any kind of food you eat, so this ad's claim that you need to eat sugar is sort of a complete lie.
(Aside: Diabetes is the result of a berserk immune response, so don't let anyone tell you that a given bogus food supplement is helpful because it "boosts immune response". When your body's immune response is "boosted", it attacks your own body. Aside to the aside: Calling something a "food supplement" is an easy dodge of any and all government regulation. Food supplements need to show no proof of efficacy or safety to be sold in the marketplace They are self-monitored, which is to say, they run on the honor system. The FDA claims the responsibility to come down on dangerous food supplements only AFTER they come to market and are being sold to people. Clap, clap. "Supplements" enjoy a special set of very slack regulations. Food and actual medicines are much more tightly controlled.)
he whole thing about a "sugar rush" is a myth. The more likely explanation for kids' freaky behavior at holidays and birthday parties is that, on these occasions, kids are overstimulated by having a bunch of friends around and opening presents. The intake of sugar at these wingdings is coincidental. There is no scientific evidence that sugar in any amount will make a kid behave like a ferret full of espresso. But, people never let evidence get in their way of believing whatever they want to believe. It is somehow reassuring to know that advertisers have been lying to us as long as there have been advertisers, don't you think?
In all likelihood, the boys in the ad are just happy to have the war over with, and excited to be wearing such tiny pants.