I'm not sure how many times I've been here, but it's a lot.
I've always had an interest and an appreciation for history. Being a Phoenix native I've been curious about the area's history. I have two boys (12 and 9) who also like going here there's plenty to keep a child interested especially if you take the time to explain the exhibits in their terms.
Heard never fails to satisfy my history itch. There are a number of permanent exhibits and they change things up a bit every so often to give you a good reason to return. Visit their website to see what's going on. I don't know how many artifacts and pieces of Native American and Southwest art they have in their collection, but it's certainly in the thousands. As you stroll through the museum to see the displays and read a bit about the history you can't help but put yourself in the time period and imagine what life must have been like.
If you're visiting the Phoenix area from a location that doesn't have something like the Heard and you want to go home with some knowledge of Native American and Southwest art I highly recommend a visit to Heard.