Judith Viorst's Alexander has been cast.

From Deadline:

Disney has cast Ed Oxenbould to play the title role in Alexander And The Terrible, Horrible, No Good, Very Bad Day. The young thesp joins Steve Carell and Jennifer Garner in the Miguel Arteta-directed adaptation of the Judith Viorst book that parents read to their kids over and over. 

I don't really understand how this movie is going to be more than 30 minutes long, but whatever.