Take your students on a Scavenger Hunt around your room. Give them an engaging, hands-on way to understand this reading comprehension skill. After you have them partner up to find items to compare and contrast, have them write about their discoveries.
Cut the cards out (and laminate so you can reuse them), then have students pick two pictures that are like them and two that aren't like them. You could have students explain to a partner, or put into writing, why they picked those pictures. This is a great way for students to learn a little about themselves and each other, and it reinforces the idea of comparing and contrasting. Making these connections should help them when they look for ways to compare and contrast text.