My toddler and I enjoyed the museum. My toddler favorite things were the dinosaurs, downstairs they have a discovery section that you pull down a lever to hear the sound of a dinosaur, looking at the mirror and comparing the size of himself to the dinosaur, and digging for fossils.
This is a 1-2 hour museum. Not crowded.
What we did to make it a day was go to Memorial Park in Claremont and had a picnic lunch - they have a wading pool for the kids during the summer months from 11:30am - 1:30pm. After lunch headed over there.
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