I would implement this picture to engage my learners in thinking critically by asking them questions like: "why are these objects classified as solids? What makes you able to know these objects are solids and not liquids? What do all of these solids have in common and how do you know that?" "How do you test or determine is something is solid?"
I would implement this picture to engage my learners in critically thinking by asking them to observe what is in the glass. Then I would state a few questions such as, "How can you tell by looking at the glass, whether the item inside the glass is a liquid and not a solid? How does the liquid inside the glass differ from the actual glass itself and how do you know? What are some properties that all liquids possess, use what you are observing about the liquid in the glass to help you think deeper?
I would use these two pictures to engage my learners in thinking critically. I chose two pictures because gases are a harder concept to grasp and you cannot always necessarily see gases.
First I would have them first observe the balloon. I would ask them questions such as, What is inside the balloon that is making it expand and hold its shape like that? What would happen to the balloon if we popped it? Would whatever is inside the balloon just vanish? Observe the balloon, hold the balloon, and feel how light it is? What properties do gases possess and by looking at this balloon how do you know?
The next picture I would use to engage my learners in critically thinking is asking them to look at the steam coming out of the pot. I would then ask them questions like, "How does this gas differ from the type of gas that was inside the balloon? Are they actually different or are they the same? How do you know? Can gas possess and take on many forms, yes or no and how do you know? For a more trickier in depth question I would ask, "Also, what/ how was this steam created?"
I would use this last picture to engage my learners to think critically by having them compare the three states of matter side by side. I would ask them questions like, "What, if any, do these three states have in common? Which two states have the most in common and how do you know? "Can you turn a solid to a liquid? Liquid to a solid? Liquid to a gas? How could you determine whether or not you can do those three things? What drastically differs all three of these states of matter from one another?