You can keep some green in your wallet this holiday season by adding some fuel to your brain with these free family friendly science events offered throughout the Chicago area. Head out to any of these events and learn more about the human body, the environment, the planets and much more. Don't be surprised that as temperatures drop, your IQ keeps rising.

Roosevelt University | Dec. 6, 9 a.m. - 12 p.m.

Kids ages 9 and up are invited to participate in "Science Exploration Day" at Roosevelt University. Here, Roosevelt professors and graduate assistants will help kids participate in one of three science workshops. Investigate how scientists collect DNA at "DNA Detectives." See what the world looks like from bacteria's point of view at "Microscope Mania." Learn how plants reproduce oxygen at "Fun with Photosynthesis." All workshops include hands-on learning activities.

University of Chicago | Dec. 6, 10 a.m. - 4 p.m.

Tour science labs, hear lectures from different scientists, watch experiments and participate in interactive physics demonstrations at the University of Chicago's "Physics with a Bang! Holiday lecture and Open House." Lectures and demos are from 10-11 a.m. and 2-3 p.m.

Millennium Park | Dec. 6, 10 a.m. - 11 a.m.

Come out for a "Winter Garden Stroll" at Millennium Park, where you'll tour the famed and lush Lurie Garden. You'll also get a chance to unravel the life cycles of plant life and learn what inspired the garden's design.

Illinois Institute of Technology | Dec. 12, 3 p.m. - 5 p.m.

Visit IIT for the "Weird (Electronic) Science" presentation with live demonstrations. Budding video-gamers will also learn how to build their own electrical circuits with tips from a former U.S. electronic warfare officer. For ages 13 and up.

McCormick Place | December 27 - 29, 10 a.m. to 4 p.m.

Stop in at Mayor Daley's 9th Annual Holiday Sports Festival at McCormick Place. This three-day event incorporates live demonstrations where guests can participate in 40 different sports zones including: wall climbing, golf, gymnastics, skateboarding, volleyball and a special tots zone for tiny sports enthusiasts. At the LABFEST zone guests can experience sports through interactive science presentations.

Garfield Park Conservatory | Every Saturday and Sunday through Dec. 31

From 11 a.m. through 4 p.m. families can spend some time at "Get Ready! Get Set! Grow!" an interactive exploration of plants. The 1 p.m. to 3 p.m. slot is especially valuable for families on the go, offering Make-and-Take activities for little ones to learn on-sight or at home. Upcoming projects include "Make a Winter Orange-a-ment" and "Holiday Scent Necklaces."

Museum of Science and Industry

And as a treat, here's an event that's worth the green you pay. If it's science you're looking for, then a visit to the Museum of Science and Industry is just the ticket. Round up the kids for a day-long exploration of health, science and the environment. And don't forget that the greenest home in Chicago, the Smart Home: Green + Wired exhibit, is only running through January 4 at the MSI. This tour showcases cost-effective methods for sustainable home design and gives guests tips on how to make their homes more energy-efficient.

As an added bonus, now through Dec. 11 (valid Monday - Thursday) print out a voucher at the MSI website when you buy one adult general admission ticket and get another adult ticket for free.