Building a Sandbox

Ok... so I have discovered that my sweet little Addison LOVES to dig.  She currently digs in our backyard.  She calls the nasty dirt near the edge of our house, her 'sandbox'.  We recently went to Pensacola, FL and played at an AWESOME playground... COVERED in sand!  Let's just say, Addison (and Wyatt) had a BLAST! 

So... the 'plan' is... I am going to make a SANDBOX for the girl (and boy).  Will is out of town ;-)... so, he can't help me out on this one.  The only 'obstacle' is that I will have to build a sandbox WITH a lid.  You see, we have cats... BAD!  AND... we are one of the only houses WITHOUT a dog.  So, I think the cats like our yard the best...UNFORTUNATELY! 

I have googled building a sandbox and have found a few plans.  I think they're all pretty similar.  I'm heading to HomeDepot/Lowes (have to do some comparative shopping and save some money) tomorrow.  Who's excited to come along??  Stay tuned for a sandbox update...