Earth Day activities

Minneapolis cleanup, 9:30 a.m.-noon Saturday

• Volunteers are needed to help clean up parks during the 23rd annual Earth Day Cleanup. No registration is needed. There are 37 cleanup sites around the city. Go online to minneapolisearthday.com for a list of sites. (612-230-6479)

St. Paul cleanup, 9-11 a.m. Saturday

• Volunteers are needed for the city's annual spring cleanup. Volunteers are encouraged to register and pick a cleanup site. Gloves, bags and snacks will be provided. Go to bit.ly/stpaulclean. (651-266-8989)

Wild River State Park hike, 1-2:30 p.m. Saturday

Meet at the visitor center. (651-583-2125, ext. 227)

Geocaching 101

William O'Brien State Park, 10:30 a.m.-noon Saturday

Learn how to use a global positioning unit, and then head out to find some practice caches. After the class, you will earn a special 2017 wildflower card. You can find additional wildflower cards in geocaches hidden at Minnesota state parks as part of the "Call of the Wildflowers" geocaching adventure. A limited number of GPS units are available. Reservations required; call 651-433-0500. Meet at the visitor center. (mndnr.gov)

Reptiles

Lake Maria State Park

10-11 a.m. Saturday

Touch, hold and even feed a variety of reptiles. Meet at the trail center. (763-878-2325, mndnr.gov)

Bison tour

Minneopa State Park

10:30 a.m., 11:40 a.m. and 12:50 p.m. Saturday and Sunday

Ride through the bison range with the naturalist and get an update on the herd at the park. Registration required; visit mndnr.gov/reservations or call 866-857-2757. Tours are $8 for adults, $5 for ages 5 to 12 and free for children under 5. Tours start at the group campground on the campground side of the park. (507-384-8890, mndnr.gov)

Bird banding

Lowry Nature Center

9-noon Saturday

Birds will be safely trapped, studied, banded and released. Drop in anytime. (763-694-7650, threeriversparks.org)

Archery for families

Baker Near-Wilderness Settlement

1-2:30 p.m. Sunday

Learn the basics of shooting a bow and elements of safety while shooting at traditional and 3-D animal targets. Equipment provided. Cost is $10. Call 763-694-7856 and reference activity #230341-00. This program is for ages 8 and older. (threeriversparks.org)

Nature hike

Eastman Nature Center

1-2:30 p.m. Sunday

Search for natural surprises on a casual trail hike. Children 17 and younger must be accompanied by an adult. (763-559-7700; threeriversparks.org)