I will ask the team to grow a plant (that needs water) with 150 mL of water bottle. Within few weeks, they observe the plant stops growing and dies.
Now, I will tell them the need of renewable resources to sustain in this world. With fossil fuels (like 150mL bottle) we can only meet energy demand for few more decades, if we want to meet the future need, we need renewable sources (like continuous watering of plant). I guess this small activity would ignite and engage their mind.
