Provide time for the students to trade objects and test for magnetic properties by using a magnet.
(the students; to trade; objects and test for magnetic properties) Context(the students to trade,List([17, 38))):(the students; to trade objects and test for magnetic properties by using; a magnet)
the students to trade,List([17, 38))
the students the students
to trade to trade objects and test for magnetic properties by using
objects and test for magnetic properties
a magnet