While practicing with Alai and the others from his launch group, Ender comes up with a lot of ideas that other armies have never tried. How do they come up with their ideas? What does this teach us about creative or innovative thinking?

As Ender gets a little ways into his Battle School education, he and other soldiers begin taking advantage of extra Battle Room practice time.  Ender definitely begins changing the way that he and his fellow soldiers think about the zero gravity battles.  The biggest change in tactics that Ender stresses is that the enemy is down and not forward.  This causes a complete rethinking of body positioning in relation to the enemy.  Many soldiers are against Ender's ideas, at least, at first.  They do not like changing the status quo. However, when Ender's new tactics end up working more often than not, other students begin putting more confidence in Ender.  The way that he comes up with these new tactics is basically trial and error.  Ender is a tactical genius, but he still has to try out his new ideas.  Some of them fail and many of them work, but trial and error followed by minor tinkering is the main method of discovering new tactics.  

But he put new touches on the patterns, made the boys try the maneuvers with one leg frozen, with both legs frozen, or using frozen boys for leverage to change directions.

This part of the story is a great sequence because it reinforces to readers that creative thinking involves testing.  It is one thing to think that something might work. However, you cannot know until it has been tested.  Additionally, this part of the book shows readers that failure is bound to happen, and that is okay.  You learn just as much from failure as from success.  When an idea fails, you have been given evidence of something that does not work.  That is valuable information because it tells you about an idea that should be avoided in the future.