The first animal to be completed was the camel.  He had some trouble walking and a couple of the kids tried to redesign the gearing mechanism.  When that didn't seem to be working I posted a question in the NXT forum and Faye answered and provided some ideas.  The camel walked better, but it was always a bit of a challenge.

The bunny was easy to build and hopped around nicely for 3 weeks, including the morning of the science fair.  But when we arrived, it wasn't working as well.  We had brought our own surface, so a slippery floor was the problem.   The problem seemed to be that the motor was rotating too much after the first hop.  They tried changing the program, but it just wasn't the bunny's day.

The spider was amazing.  Our team was getting low on parts the first time it was built.  They substituted a crown gear for the 24 tooth gear which was almost the same size.  It never worked properly and we had given up on the spider.  A few days before the science fair, a team member from last year said she'd like to use her NXT set to build an animal for the zoo.  She had the right gears and the spider walked much better.  The spectators had fun watching it creep along and then back up and change direction when it found an obstacle.

The skunk was very popular.  Partly because of the blunt shooting out when the tail lifted, but also because it was on wheels.  The skunk could move around faster than the other animals which made it interesting to see where it would go next.

I loved watching the elephant lift up it's head and roar.  Adding the elephant sound gave the kids a reason to find out how to edit sound files and then add them to the NXT.  It wasn't something they had ever played with before, but it was fun.

The Stegosaurus was great.  He was the most reliable of the walking robots, always just plodding along.

What a great way to get them interested in robots!  Thanks to Faye Rhodes for a wonderful idea.