Students learn by doing! This resource has 24 cards that can be is a self correcting activity for student to learn about mutualism, commensalism, and parasitism. I use this in my class as a group activity. Students work in groups to first pair the cards based on the picture and short description on each card. They then sort the partners into the following categories: mutualism, commensalism, and parasitism.
I have done this activity many times and I am always amazed about the conversations students have. They make great connections between what each animal/plant provides and what they need. Towards the end students start to see that each card needs a partner and each category has 6 pairs. If their are any mistakes in the activity the students it becomes obvious and the students can make adjustments on how to complete the assignment correctly. They do a good job "struggling" through the assignment and at the end they feel validated as if they solved a puzzle rather than complected another worksheet in science class.