The white with Blue is what you can find at Barnes and Noble. We used those for 2a and 2b. Ds6 is now working through 3a. We bought the text and workbook online. I really like the textbook. I don't think we really need the workbook, although it is giving us extra practice that I send with him to morning daycare to work on after we go through the textbook selection.
I do recommend using the Singapore placement tests. Ds passed the 1a and 1b tests. We did not give the 2a test to him but started him on 2a (he is in kinder) this past fall. He is now in 3a which still seems quite easy for him. In 2a and 2b, we did not skip anything. In 3a, I feel more comfortable (maybe its because we have the textbook) reviewing in the book and doing a few problems and not all. If its mastered, we continue on.
