Hi Jennifer,
Welcome back to the Disney Parks Moms Panel! Clearly, you are doing some stealth vacation planning!
Unfortunately, there is no way for us to know the exact cause of the price increase for the dates of your trip. I can say that we typically visit the Walt Disney World resort in the summer and I have occasionally noticed some dramatic price increases after we have booked our trips. Your planning has paid off with getting a better price. Our resort experiences have always been terrific and we have not noticed any particular overcrowding despite being there in the summer when schools are typically not in session.
Animal Kingdom Lodge is a beautiful resort. I have stayed there a few times and each time I appreciate it more. The savanna view rooms are stunning. I woke up one morning and there was a giraffe right outside of my window! I also have watched cast members leading children's' activities and the kids looked like they were having a blast.
Since you will be staying so close to Animal Kingdom theme park, I do hope you plan to visit
Pandora - The World of Avatar. Both Na'vi River Journey and Avatar Flight of Passage are amazing experiences. If you have little ones with you, be sure to stop by the Colors of Mo'ara kiosk. I was impressed with the artistry of the local expats. Close to Kilimanjaro Safaris we also love to watch the wood carvers. On our most recent visit, we saw a craftsman from Nairobi, Kenya hand carving a walking stick that was simply gorgeous.
Jennifer, I would not worry too much about crowding at the resort. The resort is spacious and has lots of room for exploration.
I do hope you take lots of pictures to capture the adventure!
Magic, memories and Minnie Mouse hugs,
Donyell