Spend and hour or so cooling off in Pennypack Creek or one of its tributaries as we turn over rocks in search of the creatures that call the creek their home.  A staff person will lead this aquatic safari in search of water pennies, whirligigs, and other exotic denizens of the water world.  Footwear that can get wet (e.g., old sneakers or water shoes) strongly recommended because we’ll be wading in water with slippery rocks.  Bring an old towel to dry off afterward, too.  This program is geared towards children.  Limited to 20 stream walkers; reservations required.  Members free; non-members $5.