This looks like one of the easiest water walls I've seen. Fun with water, great recycled plastic bottle project.
A Small Contemporary Garden - Woodpecker Garden and Landscape Designs. Ideal for a small back yard
I love this idea for making mini truck tunnels to create a little construction site in your backyard. (Link goes to list of other outdoor fun ideas for kids--outdoor kitchen)
Homemade water wall for children to play with water in the garden.
DIY Wooden Roads and Ramps for Toy Cars: Easy homemade car tracks perfect for outdoor and inside play- especially fun for Hot Wheels fans! Great for school or home.
25 Outdoor Play Areas For Kids Transforming Regular Backyards Into Playtime Paradises Guauuu llego tarde para mis chicos .