I got called in for a group interview about 2 months ago. I was asked around 10 thought-provoking questions, mostly situational. About 1 month after my interview I received a call with an offer, I immediately accepted. The hiring process was pretty lengthy - I had to get both a child abuse and FBI clearance (which was paid for by TSA), complete a 3-hour long online program on recognizing child abuse, and provide 4 references (2 professional, 2 personal). So in total it took about 2 months.