we used the 6-8 ages curriculum exclusively when my son was in first grade. we completed the entire course for that year (even with delving in deeper here and there). for second grade this year, we've tried some new curriculums (not working) and are supplementing with some of the MBTP 7-9. when i was preparing for the start of second grade, i reviewed the standards for our school district for second grade. based on what we did for the 6-8 curriculum, we had already covered ALL of what the second graders in our district would be covering. completely ahead of the game!!!