In the final scene, the amount of fake snow in Sara's and Brandon's hair changes between shots.
When Sara and her mother go ice skating the thermometer in the rink shows -32°C, but when Sara says it's "32 [degrees]" she most likely means +32°F. The shown temperature, -32°C, would be unreasonably cold for a skating rink, but +32°F is at the colder end of a normal air temperature range and makes much more sense.