When my grandsons were small I would buy the Lego Block kits that I liked and then volumteer to help put them together.
When you find the cache take a minute to look over the cache before trying to solve.
To get the code to open the lock you will need to count each color of blocks that you see on each side. The fewest total blocks of a color on all 3 sides added together is the answer, then encrypt that answer. Corner blocks of the same color will be counted on both sides.
There is a small grass covered hill to walk up to get to cache. The grass is kept mowed.
Permission granted from church pastor to place this cache.