I was first challenged in this area by a friend leading a session in a parent / toddler group I attended when my son was younger. (premierchristianity.com)
This was at first challenging because I live 2500 miles from my closest friends, but I keep up with them in other ways. (theinspiredroom.net)
Even the very first challenge levels were quite difficult, so it's definitely going to keep players busy for a while. (stevivor.com)