"These are the words Moses spoke to all Israel in the desert east of the Jordan--that is, in the Arabah--opposite Suph, between Paran and Tophel, Laban, Hazeroth and Dizahab."
(Deuteronomy 1:1)
What's important here, kids? Is it that the location given? Yes, that is important. But even more, it's the words that were spoken while Moses was in the location "in the desert east of the Jordan" - the Words of the Law that were given to him by God!
Deuteronomy comes from the two Greek words meaning "second" and "law." Before Moses was no longer with the new nation of Israel, he retold the laws that were given during the years in the desert. This retelling was from Moses' heart; he was as a grandfather telling the children he loved to never forget the Laws that were given to them.
Why?
Because only through these laws would they recognize God's Salvation - the Word, the Lord Jesus Christ - when He visited the earth!