To reinforce the concept of magnetic and non-magnetic objects, put both types of objects out for them to test before attaching them to their fish.
(them; to test; T:before attaching them to their fish) Context(them to test,List([97, 109))):(them; to test before attaching; them)
them to test,List([97, 109))
them them
to test to test before attaching
T:before attaching them to their fish
them