Calcrostic style questions are very common on Caribou Math Contests. Here are video solutions to several questions of this type:
April 2013, grade 3/4 question 11
April 2014, grade 3/4 question 12
October 2015, grade 3/4 question 11
November 2012, grade 5/6 question 18
There are also a lot more tips and suggestions available here:
After watching a couple of solutions, try out the interactive calcrostic puzzle here: