Katy is reading "Outdoor Safety & Survival" (1997) published by Douglas & McIntyre Ltd.
This is the only episode between Episode #22.9 (1999) and Episode #24.20 (2001) in which Aidan David (Arnie) does not appear.
Amy and Anika's fan letter to Colin is written in the same handwriting as Dill's postcard to Arnie in the previous episode Episode #23.13 (2000).