My oldest child is just completing first grade.
For math, we are using the Singapore math curriculum, Primary mathematics, level 1, US edition, which we absolutely love. Our son is thriving and we could not be happier. We use the full curriculum including the Intensive Math Practice and Challenging Word Problem books which are excellent.
For English we are currently using Abeka. While I believe that the curriculum itself prepares students quite well, I have to modify it extensively. The curriculum is written for a classroom environment which means that there is an immense amount of disorganization disguised as repetition. Additionally, I have found that I do not like a fully scripted approach. What I like so much about our math curriculum is that it is written specifically for homeschoolers. The concept to be taught is introduced with a few ideas for teaching it, and it is up to the teacher to determine when the student has mastered the material. Workbook pages are then assigned to verify mastery of the material. I wish this same approach was used in English.
For all other subjects we are also using the Abeka curriculum. It is extremely light on content, but I believe that during the first years, K-2/3, the main focus should really be on providing an excellent foundation in both math and English.