KULI'OU'OU — From the 'āina to the wai, employees, military members, students and the elderly yesterday transformed themselves into environmental activists on Earth Day, and President Obama's sister told a group of invasive algae pickers that everyone can learn from their example at Maunalua Bay.

At the edge of the bay, Maya Soetoro-Ng said she was inspired by their work to clear the once-pristine Maunalua Bay of invasive algae and pledged to join their effort to pick leather mudweed one handful at a time.

The ongoing work at Maunalua Bay — just one of dozens that was highlighted across the Islands on Earth Day yesterday — is the direct result of the economic stimulus plan pushed by Soetoro-Ng's Honolulu-born brother, President Obama.

"Every single one of you is an educator," Soetoro-Ng told the algae pickers hired by Pono Pacific through Obama's stimulus plan. "... You are passing something tremendously important on to my children and all of our keiki. ... If government can help a little bit, that's great. If government can at least get out of the way, that's great. ... But everyone can at least realize that the power is in our hands."

Other Earth Day efforts saw students, employees and faculty at the University of Hawai'i–Mānoa planting trees, shrubbery and native vegetation along walkways and bicycle lanes leading to the Stan Sheriff Center and soldiers.

Today, soldiers at Schofield Barracks plan an Earth Day Festival. And Mayor Mufi Hannemann reminded people about Sunday's shoe recycling effort from 9 a.m. to 2 p.m. on the grounds of Honolulu Hale.

Any brand of used athletic shoes — except those with cleats — will then be recycled into play and sports surfaces.

"This is a wonderful opportunity during Earth Month to show that we care for our 'āina," Hannemann said. "By recycling our old basketball and jogging shoes, we are reducing the amount of opala that would otherwise go to our landfill."

At Maunalua Bay yesterday, Soetoro-Ng presented an "environmental hero" award from the National Oceanic and Atmospheric Administration to Mālama Maunalua, a community-based group that has dedicated itself to restoring the bay.

The employees of Pono Pacific then waded into the ocean to get back to work ripping invasive algae from the muddy sediment in the bay's shallow waters.

Since February, the workers — who call themselves crew members or crew leaders — have spent hours every day in sometimes chilly water bending over to remove leather mudweed, building up shoulder, back, arm and leg muscles in the process.

To have the president's sister cheer them on yesterday "was very motivating," said crew member Leilani Warren, 23. "It's a privilege to have her come and say she's grateful for our efforts."