"Without Language, Large Numbers Don't Add Up" (Feb. 9, 2011)

See Jon Hamilton's story on NPR

In 2004, researchers published data on two Amazon tribes whose members' vocabularies did not include precise words for big numbers. Recent studies show that language affects our understanding of numbers.

To students: Think of other things that might not be possible if there is no vocabulary for it? Do not worry about evidence or if there is existing research. Imagine an hypothesis that you would be curious to pursue.

Challenging 10 Myths About Second-Language Acquisition (Part 2)

5.
False: Students learn what they are taught.
True:   We know from experience that students don't learn everything they are taught. Refer to  Krashen's Natural Order hypothesis. Fortunately, students can learn a great deal that no one ever teaches them. They are able to use their own internal learning mechanisms to discover many of the complex rules and relationships that underline the language they are learning.

6. 
False  The best predictor of success in second-language acquisition is motivation.
True   We know that learners who begin to learn a second language as adults rarely achieve the fluency and accuracy that children do in first-language acquisition. This should not be taken as evidence that adult second-language learners are not motivated to learn. Age and other factors could be the reason for different learning outcomes.

7.
False:  The earlier a second language is introduced in school programs, the greater the likelihood of success in learning.
True:   The decision about when to introduce second- or foreign-language instruction must depend on the objectives of the language in the particular social context of the school. When the goal is native-like performance, then it might be desirable to begin exposure to the language as early as possible. But if the objective is not native-like performance, it can be more efficient to begin second-language instruction later.