Saxon's Math Intermediate 5 can be used in place of Saxon Math 6/5.

Saxon's incremental lessons provide daily practice and assessment in a "spiral" format; mathematical concepts are taught through informative lessons, diagrams, interactive activities, and investigations that build critical thinking as well as real-world problem solving skills. Saxon Intermediate 5 includes 12 sections, 120 lessons and 12 "investigations."

Textbook lessons are divided into three sections. The first section is "power-up practice," which is designed to improve speed, accuracy, and the ability to do mental math. The second part of the lesson is the "New Concept," which introduces a new math concept through examples. Thirdly, the "Written Practice" section reviews previously taught concepts through 25-30 problems in each lesson. One "Investigation" per 10-lesson section is included; "Investigations" are variations of the daily lesson and often involve activities that take up an entire class.

See more info here...

Note: My Math Assistant does not sell the Saxon books directly. If you make a purchase using the links on this page, My Math Assistant may make a small commission on the purchase as an affiliate of The Christianbook Group.