There are not many things that are better than free movies, being outside, summer time, and being close to the ocean. In the summer, usually on Tuesdays in July and August (check their website), this is exactly what happens in Stanley Park.
If you're exploring Stanley Park, and looking for something to do in the evening afterwards, this is a great free, family-friendly, and fun thing to do. The movies selected usually appeal to a wide variety of people.
Parking is free after 10 pm, but arrive early: otherwise, you will not get a seat in front of the screen.