So, this is for one of the Zenon movies that Disney Channel used to air. The title character (who I believe is from a base in space or something) is in a school on Earth in a science class, and the teacher gives the class a temperature to heat a beaker to. She heats it to whatever that is in degrees Celcius. The beaker explodes, and the teacher berates her by saying, "Here on Earth, we still use Fahrenheit." This is a science class. You always use metric measurements in science class. Not to mention how this totally ignores the fact that there's only one country in the entire world who doesn't have the metric system as their standardized system of measurement, thus rendering the teacher's statement extremely ignorant. This isn't even Hollywood Science, this is Critical Research Failure.
The movie takes place in the future. It's possible that people don't use the metric system anymore.
...but it's not even that far in the future. A year that all things considered isn't even that far off. And it's not exactly logical that the entire world would abandon a system that works and always has worked when only one country in the whole world uses a different one and when they still use the metric system in outer freaking space.
The earth scenes take place in the United States. While it's still really dumb for a science class in the US to use Fahrenheit, it's somewhat less Critical Research Failure because yes, some Americans really are ignorant enough to use "earth" to refer to the US and assume that Celsius would only be used in space or in labs, and not lowly science classes. Granted, it's still dumb and ignorant, but it shows you just how much the writers don't know anything about science.