J.N.
We sold our home last September and had similar problems. Our Daughter had just turned one when we put the house on the market, so the clean up included dealing with her large play equipment. To keep the mess down we packed up all of our nonessential stuff and put the clutter we had collected in a storage unit. Lots of my husbands RC and gas powered toys went into storage as well as extra furniture. I also packed up my art supplies and drafting table, a major sacrifice for an artist.
The best advice our real estate person gave us was to keep the major areas like the kitchen counters clear of stuff. We also stopped putting magazines and newspapers in the living room. The one thing I wish we had done was to break down the extra bed in our daughters room. With that bed and the crib in the same room it made the space feel small.
Hang in there! Selling a house is tough, but once you are done and in your new home it is definately worth the hassel. Oh, be sure that they give you enough notice when they want to show YOUR home. I had a couple of realators that gave me a hard time about wanting to see the house immediatly because the were "in the area". It caused a lot of hassels for us. Six times I was called at work to go home and get out two dogs out of the house. On weekends they would call just after lunch or just after my daughter was down for her nap. You know the kicker was that after knocking myself out to accomodate these people none of their clients ever made an offer. The gal that bought the house saw it the first time with our agent. So, keep the faith and remember you have a life to live while the house is on the market.