I have 1A and 1B for this year. I use them to help me decide what scope to do.
I mostly use this day to day: http://www.math-drills.com/
I also pick a different sequence. I believe in solid mastery and I think in the 1st grade level and my children's own development, Singapore is a little too conceptual and jumping-around for my taste.
E.g., what we did today was this:
One line (about 8 problems) 2-digit addition with regrouping. This reinforces addition facts, as well as cementing the regrouping algorithm in her head. She's been doing two lines for a while so it's time to add another skill and back off the quantity.
A set of subtraction problems using a number line from -15 to +15. I generally just write out the problems myself. You can draw a number line or print them out. Generally I will give 8 to say, 12 subtraction problems sometimes with addition mixed in.
Two lines (about 16 problems) of < > = comparisons using the symbols. Today was the first day we introduced those symbols. DD had no trouble with the concept or remembering them, but we will drill perhaps a fast line of them every day for a while so that she does not need refreshing later.
I don't find this kind of drill takes very long. I would rather have a very tight scope with a logical sequence than jumping around.