As recent as 2010 it has been said that 97% of Americans believe that education in science and space technology along with engineering and math are probably the most important areas in the US for the future of the economy. This is why it's important to help children get more interested in some of these topics. You can do this by getting them involved in science games so that they are allowed to learn by active participation.
You can find games to help teach kids about energy and water by playing games at the site Energy Kids where they offer not only information about energy through games but also through different riddles and quizzes. This information is easily accessible to students of any age. There is also a site called the International Aid Organization Water Aid has games that will teach students about water and the importance of sanitation. For example in the game called Pani the Hand Pump, the kids will pick which country they'd like to visit from the choices of Ethiopia, Nepal and Ghana. The goal here is to try and figure out how to solve their water problems in the villages of these countries. Each time a child comes up with the right solution they'll move onto the next screen, but if they choose the wrong solution they will lose a bucket of water. The goal is to end the game with at least one bucket of water left.
If you want your students to learn about animals and the human body a good site based in the UK called Crickweb is a good one. It has a variety of different games and activities for younger kids. Some games will group different animals together for the kids to learn about and then there are also games that examine the human body and different animal skeletons. There is also National Geographic Kid which has a great selection of topics for games that include recycling, animal games as well as space games. One popular game is Frog Flicker which teaches students about what a frog eats. The goal of the game is to flick the tongue of the frog to catch the bugs that he eats. In the grass however is a snake hiding and the kids have to catch the bugs before the snake catches them.
The NASA Space Place is a great place that has a huge collection of different space technology games and different animations about the earth, technology and space itself. The facts and different animations should be studied first before the students try to play the games that are offered. They will be better able to play the games if they check these things out first. On game they offer is called Load the Shuttle where the students need to figure out and plan what kind of equipment they will need to load for their mission. If they make the load to heavy they will be told to figure out a solution to solve their problem.
The Nobel Prize Organization site is a great site for older kids and they offer games as well as simulations that are based upon Nobel Prize achievements. They provide great background in the games as well. Some of the game topics include chemistry, medicine and physics. There is a game called Diabetic Dog where the child is the caretaker of a dog that is diabetic and they learn through this game how to treat diabetes. Another good game that can be found on this site is the one called Immune Responses which will teach the students how the immune systems works and ways our body's immune system helps us and protects us.