You would normally think that adults, being older and wiser, would be better suited to learn a new language than a five year old that is still learning English. After all, the adult brain is full of knowledge and more aware of the world. However, this is not the case. Children are much quicker at learning a foreign language because their brains are still forming and accept new information much easier. It has actually been proven that the younger a child is, the more susceptible they are to learning new things, because their brain is that much more pliable at a younger age.
In previous years, most U.S. schools required Spanish or other language classes at the High School level, and often were fraught with students who couldn't learn or experienced difficulty succeeding because their brains were already pre-programmed with too much other information. Many people are successful at learning Spanish at this age, and even into adulthood, but the learning methods are completely different. When children are taught a foreign language at an early age, they learn in a method that works for their brains, and many language learning programs are trying to replicate this learning process.
Kids look at picture books and watch television, picking up the names and ways to say things from their parents and other adults around them. For example, if you sit down with a child and show them pictures of farm animals, eventually they learn the names of these animals based on what you tell them. Spanish learning works best when it is done the same way. For years, people have been teaching adults and teens foreign languages based on translation and vocabulary based methods, which is not as efficient as reverting to the brain's natural learning process.
Children's brains are much more pliable than adult brains, which is why they learn Spanish quicker and easier. Also, the methods used to teach children are more natural than the memorization and vocabulary based methods used for adult and high school Spanish education. Learning a new language is never easy, but the method plays a large role in the overall difficulty of the process. This is why children learn Spanish and other languages much faster than adults. They are taught in a natural learning method and their brains are young enough to absorb information more easily.
Adults can learn Spanish with the same ease that children do, through different teaching methods. By using conversational speech and image recognition instead of boring lists of vocabulary translations, you might have a better chance of learning Spanish than you did before. Many people are now realizing how much better the methods used to teach children are, which is causing many schools to change the way they teach foreign language classes so that more people succeed. However, because of the methods used and the malleability of young brains, children still learn faster than adults when it comes to foreign languages, and probably always will.