The month of May is national "Bike to Work" month, and this week the League of American Bicyclists is encouraging people to leave their cars parked and get on a bike for the morning commute to work or to school!
The environmental and energy benefits of a pedal-powered commute are obvious, and you might save a few dollars when you puts your pedals to work instead of your engine. There is, of course, a bit of a trade-off in terms of speed. You'll need to allow a little extra time, depending on how far you need to go.
If you want to figure out a strategy for maximum speed (keeping safety in mind!), then you need to dig deep into gears and the impact of gear ratios on speed. There's a reason your bike has multiple gear and speed settings!
The Science Buddies science fair project "Jack and Jill Went Up a Hill and Came Biking Down After" helps uncover the relationship between gears and speed.