Hi Jewell, I'm not sure where you're looking on the website, but under the "Hours & Admission" section (http://dsc.smv.org/hours-admission.html) it lists admission for children aged 4-12 as $6. Given the staff size and popularity of the museum, the butterfly garden is not staffed around the clock. As outlined on the signs on the fence to the garden, if you discover it locked, please contact a staff who will be happy to assist in your visit to the butterflies. I do hope you will try the garden again (free to visit without paid admission) and am sorry you're experience was not as hoped.
The cost of admission for children above the age of 4 is $6 and as far as the butterfly garden, you have to inquire about it if their isn't anyone standing there. They have to make sure that the doors aren't left open to insure they don't get out or other creatures get in. Hope this helps you.
You have to ask to see the butterfly garden as they have procedures to keep the non native specimens inside.
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