These experiments are suitable for high school students.
 

• Build a bridge
• Materials under stress
• Mouse trap vehicle
• Software protocol
• Transistor experiments

Here are other websites with additional activities:

• http://www-mariachi.physics.sunysb.edu/wiki/index.php/High_School_Experiments
• http://www.eweek.org/site/DiscoverE/activities/classroom_archive.shtml

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