Both my sons go to Challenger. They started at 2.5 years old. My oldest is now in Kindergarten. He reads everything, EVERYTHING. Even big words because he can sound them out. Sings all the phonics. Knows how to do complicated math (for this age). Can't believe how much they know. He's working on his science project now. They need to generate an hypothesis and build a science display. He's 5 years old! My 4 year old is also reading books and has great penmanship! He's doing math too.
Every teacher is amazing. The director is very kind but stern with the rules. I love it.