Fossil field trip

Whitewater State Park

10 a.m.-noon Saturday

Find fossils of plants and animals. Transportation needed. The site is 9 miles from the park. (507-932-3007, www.mndnr.gov.)

Fish printing

St. Croix State Park

11 a.m.-5 p.m. Friday

Stop by the St. Croix Lodge for the activity. The park's fourth annual "Ectothermathon Weekend" continues on the weekend with more attention to coldblooded creatures. (320-384-6591, www.mndnr.gov.)

Geocaching

Interstate State Park

1-2:30 p.m. Saturday

Meet at the park office (use the park's campground entrance). (651-465-5711, www.mndnr.gov.)

Campfire contest

William O'Brien State Park

10:30 a.m.-3 p.m. Saturday

Learn recipes and get tips, and then take part in the "Chomped" competition. You will have two hours to build a fire and design a menu from the secret ingredients provided. (651-433-0500, www.mndnr.gov.)

Family log rolling

French Regional Park

1-2:30 p.m. Sunday

Improve balance, agility, concentration and core strength in a sport with a long history. Cost is $15 and there is a 20 percent discount for groups of four or more. This program is for ages 5 and older. Children 17 years and younger must be accompanied by a registered adult. Reference activity number 325001-01. From 3-4:30 p.m., there is a session specifically for girls and women. Reference activity number 325001-00. (763-694-7750, threeriversparks.org)

Yoga on paddleboards

Fish Lake Regional Park

9:30-11 a.m. Monday

Use a stand-up paddleboard as your mat and take yoga to the water in this fun but challenging class. In partnership with YogaStudio and Corepower Yoga. All experience levels welcome. Equipment provided. Cost is $35 per class or $90 for the series. Call 763-559-6700 to make a reservation and reference activity number 325911-09. This program is for ages 14 and older. (threeriversparks.org)

Majestic monarchs

Afton State Park

10-11 a.m. Sunday

Orange, black and white, the butterflies can bring smiles to the faces of almost anyone who catches a glimpse. Discover their world in a program at the visitor center. There also will be a walk to search for eggs and caterpillars on milkweed and spot the butterfly in the field. (651-436-5391, www.mndnr.gov)