Ancient mysteries solved!

Last Friday, I decided to introduce P to addition with regrouping (what you do if the sum of the ones digits is greater than 10, as in 27+64). I carefully laid out the problem, and explained each step thoroughly. As soon as I carried the 1, P cried out, "Oh! I've been wondering about that 1 for years!" Upon being questioned, she informed me that a big kid in our old church in PA (where we lived over a year ago) had demonstrated addition with regrouping, and P had not understood it then. Interestingly, I had tried to explain the same concept about 6 months ago, but P didn't catch on and I left it for later. Half a year's growth and a deeper understanding of place value has made a huge difference. Apparently, Math on the Level's maturation-based approach works!