You can do some window-shopping at Town Center at Lake Forest Park during your visit to Lake Forest Park. Stroll along the lakeside or visit the shops while you're in the area.
Saint Edward State Park is located 9.1 mi (14.7 km) from the centre of Seattle, why not stop by during your stay. It's also full of great shops and restaurants, so you can spend the afternoon having a wander. Seattle has other popular activities such as Seattle Cruise Ship Terminal 91.