Singapore Math. This is our 2nd grade year but I felt like my DD was more suited for the 1b level so that is what we are doing this year the 1b and 2a. We will probally get to 2b over the summer.
The instruction guide was well layed out and easy to follow. Most of the manipulatives I already had laying around or found at the dollar store. There is also a helpful yahoo group that had some great card games and number bond cards. Here is the link for anyone interested. She loved it and I am finally feeling like she is confident in math. Yeah Singapore. Oh and we are using the US edition for those who want to know. There are two versions US and Standard Edition(goes along with California State Math Standards Schedule)