Maybe he is tired at night from all the fresh air and playing all day??? That is my first thought. It sounds more like a tired child if she says he is cranky. If he was going home and climbing the walls and furniture - then I would think it might be because he isn't ,oving enough.

I swear I have the most active 2 year old boy in the world in my daycare (people who see him are like WHOA !!) lol and sometimes i take him by the hand and just run up and down the side walk with him a few times to burn some steam. usually all it takes is to take him on a quiet path (where no cars drive ) and let him run or in a field. Do you have any big empty fields? baseball diamonds or soccer field near by? The kids LOOOOOOVE just being able to run free without being held or 'captured' all the time.

I have a choo choo wagon too. I love it !! Sometimes I do take the kids on long walks where the "mighty machines' are building new construction in our neighbourhood too. Just seeing the 'machines' and 'dirt piles' and things fascinates the kids and any fresh air tires them out. I take the kids on walks in bad weather and don't let them out of the wagon but just seeing stuff and the fresh air still tires them out so I think you are doing good with that.

Also.....I do set up an IKEA play tunnel and tent on certain days. The kids love running through the tunnel. I have about 5 soccer balls of various sizes and textures all over the house and the kids run and play with those. You can also go on kijiji and some people sell Step2 slides that they have used only indoors and which fold up for storage. maybe you could get a slide and put it inside the house.

Another good thing might be just to get a tiny climber and put it out in your driveway. A little climber with a slide. I have one like this that the 2 year olds flock to http://toronto.kijiji.ca/c-buy-and-s...AdIdZ273900537

But....if you tell the mom that the recommended outdoor time for kids (licensed care) is 2 hours and you are meeting or exceeding that time (including school walks, etc) then you are good. No worries. I still think the child is tired by the time they get home and therefore = irritable.
It takes a lot out of a kid to play all day, do social interactions, go outside and see different things