Saxon math is my favorite, but it can be tedious for a gifted learner.
First of all, use first or second edition Saxon 7/6. Later editions include the popular-with-teachers-but-not-with-gifted-kids "tell how you answered this question" type questions, and the leveling is not as consistent in later editions. (Meaning you might find practice problems which you have not yet learned to do, and the order of the lessons is not as incremental as previous editions).
Here's how we use Saxon 7/6 with a gifted learner:
First, finish Math 5/4 and skip Math 6/5 entirely. Why? Every lesson in 6/5 is either taught in 5/4 or in 7/6. The book is useful for kids who need a small expansion of the same topics, like with bigger numbers, but it is not helpful for gifted kids.
Then, do all of Math 7/6 in 85 lessons or less. Move as fast as you can without skipping concepts that your child doesn't already know. You can do or skip the tests, depending on how fast your child needs to get to Math 8/7, which is pre-algebra. For each lesson, do all the practice problems from every included lesson group and then either every other or every third practice problem, depending on how many problems you already did. Your kids might have greater tolerance than mine. Mine refuse to do more than about 20 problems a day, including the practice problems. Mine really prefer to do no more than 6 practice and no more than 13 problem set problems or I get math resistance and refusal, and we all hate that.
Here is our lesson sequence. You can do even fewer lessons, combining more or skipping more if your child really gets it already and is bored (and therefore resisting math).
1. Lessons 1-4
2. Lessons 5-7
3. Lessons 8-11
Test 1
4. Lessons 12-13
5. Lessons 14-15
Test 2
6. Lessons 16-17
7. Lessons 18-20
Test 3
8. Lessons 21-24
9. Lesson 25
Test 4
10. Lesson 26
11. Lessons 27-28
12. Lesson 29
13. Lesson 30
Test 5
14. Lessons 31-35
Test 6
Skip lessons 36-38 because that material is covered again in later lessons in the same book
15. Lessons 39-40.
Test 7
16. Lessons 41-42.
Skip lesson 43
17. Lessons 44-45
Test 8
18. Lesson 46-50
Test 9
19. Lesson 51
Skip lessons 52-53
20. Lessons 54-55
Test 10
21. Lessons 56-57
22. Lessons 58-59
23. Lesson 60
Test 11
24. Lesson 61
25. Lesson 63 and then Lesson 62.
26. Lesson 64
27. Lesson 65
Test 12
Skip lesson 66
28. Lesson 68 and then Lesson 67
29. Lessons 69-70
Test 13
30. Lessons 71-72
31. Lessons 73-75
Test 14
32. Lessons 76-77. Teach that is means = and of means multiply, so you can translate word problems into math problems. Teach that a fraction of a number is another number, and you can use the formula F x N = A to figure out the answers to these problems more quickly and easily than using the lesson's methodology. Likewise, a Decimal of a Number is Another number, so use D x N = A also.
33. Lessons 78-79
34. Lesson 80.
Test 15
35. Lessons 81-82
36. Lessons 83-84
37. Lesson 85
Test 16
38. Lesson 86
39. Lesson 87
40. Lessons 88-90
Test 17
41. Lesson 91
42. Lesson 92
43. Lesson 93
44. Lesson 94
45. Lesson 95
Test 18
46. Lesson 96
47. Lesson 97
48. Lessons 98-99
49. Lesson 100
Test 19
50. Lesson 101
51. Lesson 102
52. Lesson 103
53. Lesson 104
54. Lesson 105
Test 20
55. Lesson 106
56. Lesson 107-109
57. Lesson 110
Test 21
58. Lesson 111
59. Lesson 112. Teach the formula a Percent of a Number is Another number, or P x N = A. You can always use the fraction (p/100) instead of a percent or the decimal form if that makes solving it easier. Often, an easier method than the one they teach is to convert to decimal in your head and then multiply.
60. Lesson 113
61. Lesson 114
62. Lesson 115
Test 22
63. Lesson 116
64. Lesson 117
65. Lesson 118. Review P x N = A and show how it can be used for this type problem.
Skip lesson 119 (it was done in Math 5/40
66. Lesson 120
Test 23
67. Lesson 121
68. Lesson 122. Review F x N = A and show how it can be used for this type problem.
69. Lessons 123-123
70. Lesson 125
Test 24
71. Lesson 126
72. Lesson 127. Review D x N = A and show how it can be used for this type problem.
73. Lesson 128
74. Lesson 129
75. Lesson 130
Test 25
76. Lesson 131
77. Lesson 132
78. Lesson 133. Review P x N = A and show how it can be used to solve this type of problem. Translate, solve.
79. Lesson 134
80. Lesson 135
Test 26
81. Lesson 136
82. Lesson 137
83. Lesson 138
84. Lesson 139
85. Lesson 140
Test 27
Test 28
Almost everything in Math 7/6 is also taught in either 5/4 or 8/7. So don't worry about moving through it quickly. Do get the fractions stuff down solidly, though, because 8/7 assumes you know it well. Everything else is reviewed thoroughly or is a slight expansion on what is already known.
Move on from Math 7/6 to Math 8/7. Saxon did produce a Pre-Algebra book, but Math 87 actually prepares a student for Algebra better than Pre-Algebra does, and it's leveled better (the increments are more appropriate).
