Why must you make me go spelunking into that God-awful script?
In the August 21st 2006 draft, Mr Thomas still gives his Survival of the Fittest speech. This cuts between the classroom, and Wolf entering the sewers following the facehuggers. His role ends when Ricky beats up Dale after Dale taunts him about pizza delivery.
I do remember Crom saying that most of the stuff from the second day (story-wise; the day after Wolf shows up and kills Ray) was completely cut from the film; the school, Molly at the park, and a few other equally irrelevant scraps took place then.