Pauline Hanson had just two words to say when she arrived at Parliament House: "I'm back."

Senator Hanson joined her new colleagues on Tuesday for what is known as 'Senate school' - a guide to the procedures and practices that govern the upper house.

Flanked by her One Nation workmates Malcolm Roberts, Rodney Culleton and Brian Burston, the group took their place beside other new faces such as Derryn Hinch, Skye Kakoschke-Moore, from the Nick Xenophon Team, and returnee, Labor's Louise Pratt.

Official group photographs hardly make the most convivial setting for people to get to know each other but Senator Kakoschke-Moore made a beeline for Senator Hanson while Senator Pratt stood with Labor colleagues Pat Dodson and Malarndirri McCarthy.