If you believe as many do, that showing caged animals to children teaches that imprisonment of animals for some human desire (in this case "education") teaches self-interest and cruelty, then please write the Board of the North Vancouver School Distrct 44.
Send your letter to Larry Johnson, Director of Student and Program Services (who is responsible for this field trip being in the curriculum), and be sure to put that you want your letter to be sent to all Board members.
721 Chesterfield Ave
North Vancouver, BC, V7M 2M5