Excellent choice for a day trip!
The Biodome, in Montreal was an excellent choice for a family day trip while visting Montreal. It is conveniently located off the Metro, which we found to be timely, clean and reasonably priced. We found the best value to be the package plan that included the biodome, botanical gardens and insectarium. If you're interested in these sort of things set aside the whole day (you'll need it). The entrance fees were reasonable, however, as expected the concessions were typical for a tourist destination.