Jennings Environmental Education Center will celebrate hiking week with an early walk at 6 a.m. May 29. Participants will take a walk through the park and have a light snack afterward. The 1.5 mile hike will take the group through a prairie, a forest and a beaver meadow when animal activity is high. Call 724-794-6011.

Moraine State Park will be the site of "The Amazing Osprey" at 2 p.m. Sunday. Meet the park naturalist at McDanel's Launch Pavilion No. 6, on the North Shore of Moraine, to learn about this creature. "Bike and Learn" will begin at 1 p.m. Monday. Meet at the bike rental station on the North Shore for a guided bike ride. Participants can take their own bicycles or contact the concessionaire at 724-368-9011 for rental information. Dress for the weather and take water. "Native Garden Cleanup" is planned for 10 a.m. May 30. Meet at the park office on the South Shore to dig in and learn to shape the garden up for summer. Call 724-368-8811.

<B>McConnells Mill State Park</B>, Slippery Rock Township, just over the Butler County line into Lawrence County, opens the historic grist mill on Saturday. From Memorial Day through Labor Day, the restored rolling gristmill will be open from 11 a.m. to 3:30 p.m. Fridays and 11 a.m. to 5 p.m. Saturdays and Sundays. Interpretive tours, which include a corn grinding demonstration, last about 45 minutes and will be available at 1 and 2 p.m. Fridays and at 1 and 3 p.m. Saturdays and Sundays. Group tours may be scheduled by calling 724-368-3612. Other times are available by appointment. A wildflower walk is planned for 10 a.m. Saturday.

<B>Star Parties</B>, sponsored by the Amateur Astronomers Association of Pittsburgh, is planned for 8:40 p.m. May 29 and 30 at Nicholas E. Wagman Observatory. Deer Lakes Regional Park, Frazer Township, near Russellton, Allegheny County. Saturn, galaxies found in clusters and the craters of the moon will be viewed, weather permitting. Free handouts about buying a telescope will be available to point visitors in the right direction. Call 724-224-2510. Admission is free, though donations are accepted to help cover the cost of operation.