Saxon math
Saxon is the classic spiral program. Each lesson adds a small new piece and then reviews earlier material, so a topic taught early in the year is still being practiced at the end of it. The method comes from John Saxon, who taught algebra at an Oklahoma college after retiring from the Air Force and built his books on small steps and continuous review.
That steady review is exactly what a child who forgets skills over a few weeks needs, and the daily structure means a parent always knows what comes next. The same long problem sets can feel tedious to a child who grasped a topic the first time, and that child may be happier with a mastery program such as Math-U-See.
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