Ah, the “controversy” about evolution. Some people think that a scientific controversy is created every time somebody disagrees with science.
These situations are legally sticky, though. The difficulty is that the constitution doesn’t guarantee that your teacher won’t be an idiot; it only prevents him from using the state’s resources and your obligatory school attendance to cram religion down your throat. When the teacher is rather incoherent, as in this case, it becomes hard to say whether he’s just unsuited to teach or whether his asides about aliens are just an attempt to cover his religiously-motivated tracks.
But what the teacher is NOT doing, of course, is teaching critical thinking, or introducing students to any of the many interesting (and sometimes contentious) issues within evolutionary biology. If one really did want to “teach the controversy,” one would want to pick a controversy that had actual science on both sides of it – but in a high school setting, that’s going to be pretty hard to do in biology as there aren’t a lot of rip-roaring controversies that would suit the level of instruction very well.