For example, dark surfaces can get very hot. They absorb a lot of sunlight. Light surfaces, like water, reflect a lot of sunlight. Water does not get hot very fast. Dark objects also cool faster.
Some places get warmer than others.
The movements of air due to temperature differences are called convection currents. The teacher will demonstrate convection currents in water. Heat a beaker of water, allowing one edge to get more heat. To make the current visible, put a drop of food coloring into the heated beaker. You can show the effect of cooling by filling an aquarium with water.