A while ago I abadoned Singapore Math in favor of Rightstart (partly) because of the way place value was handled. It’s not that Singapore does a poor job with place value, but it is certainly not as highly emphasized as it is in Rightstart. My dd was counting to 100, but she didn’t really understand what that number meant. She had also started asking questions about how she could make bigger and bigger numbers, which led to us talking about the concept of infinity, but that is not quite relevant to this post.
In Rightstart the child learns some basic addition and then learns place value up to the thousands. There is a lot of emphasis on 1-ten being equal to 10 ones, 1 hundred being 10 tens, and 1 thousand is the same as 10 hundreds. The abacus is used, place value cards are used, and place value numbers are used in approximately 15 lessons to ensure that the child has a firm grasp on the concept.
I would like to share one of the lessons that we finished up yesterday to provide a better picture of how Rightstart treats place value lessons. In this lesson my dd had to add 2 four-digit numbers together. I had her use the place value cards to construct the numbers individually and then she combined the cards together. Whenever she had 10 cards from one group (ones, tens, hundreds, thousands) she could then trade those cards in for one card of the next value. She then had to write the result on the sheet by herself. If she had had difficulties writing the answers, then I would have used the place value numbers to construct the answer and have her copy the answer onto the page.