Research has long shown the benefits of playing games, not just for enjoyment’s sake but because they provide a vast array of educational benefits.
Students love nothing more than to play games, even if they know they’re meant to be learning from them. They like it even more if you are playing the same game as them at the same time (projected up for all to see perhaps?).
They don’t have to be just a time-filler or reward – why not let students explore content through the use of online games made specifically for that purpose?
A worksheet or question set can always be made to accompany the game if you feel it is necessary, but often students will remember content from games without having to explicitly find it. You can discuss and/or write down what they have learnt afterwards, rather than interrupting their game time.
Here is a list of websites that host great educational science games (tested and approved by my own students).
The Science Museum in London has 17 different science-based games. They are not necessarily content-specific, but rather focus on general scientific ideas and ways of thinking.
Along with a host of classroom resources, this website has a whole range of science and maths games, with the added benefit of sorting by year level. It only goes up to year 10, but no doubt older students would enjoy the simple and direct way content is presented.
Also based in London, this website has quite a few very good games focused on biology and space.
The games found here are well suited to years 7-9, but may appear too basic for older students.
While originally designed to host math games, this website has expanded significantly to include science games as well. Students seem to particularly like these ones, possibly because they are designed in such a way that the content and thought-processes within the games are well hidden.
While the website might be a bit messy, there are plenty of fantastic games and simulations here suitable for all secondary levels. A personal favourite is the Coaster Creator.