<p>One thing SAT Subject Tests can show for native-language speakers is that the language really IS your native language–thus explaining lower scores in English classes or on the critical reading section of the SAT Reasoning Test. It’s a good idea to do one more than the bare minimum of SAT Subject Tests if you take a subject test in your native language, but it’s still better to know more languages than just English, so it’s not harmful to show you know the other language.</p>