Addition in Daily Life

In the past half-year to a year, SpiderGirl has not made any particular advances in her adding and subtracting.  I have shown her a bit of grouping and borrowing.  Mostly, she has relied on the abacus for multi-digit addition and subtraction.  Since SpiderGirl has not seemed to find such computation easy, I figured that maybe she wasn't ready for this aspect of math and I didn't push it.

Why Multiplication Tables?

Although BatBoy has taken it upon himself to know exponents of 2 and SpiderGirl has been accumlating multiplication facts for some time, I can't imagine why anyone without foreknowledge of the power of memorized multiplication tables would bother sitting down to memorize 145 multiplication facts.  That's right:  the power of memorized multiplication tables.  Having multiplication facts in your head, retrievable at a moment's notice, is incredibly powerful, mathematically speaking.