I had exactly the same problem with my son. We used Abeka from grades 2-5, which is also spiral. I love the spiral approach but my son began to struggle when new topics were introduced at a fast pace. He was frustrated and began to hate math.
We switched to Math-u-See on grade 6 (Zeta) and that made a big difference for him. He still complains when he struggles with a story problem (that is a character issue) but his attitude toward math and his math skills have improved so much. He is currently using Pre-algebra and my daughter is using Algebra I.
You don’t have to worry about switching from spiral to mastery approach. Math-U-See includes a systematic review on every lesson.
