I have been doing work on developmental math for the last 4 years. I found the Ohio 9th Grade Math Proficiency Learning objectives in a good start.
Ninth Grade Math Proficiency Learning Outcomes
I. Arithmetic 1. Compute with whole numbers, fractions and decimals. 2. Compare, order and determine equivalence of fractions, decimals, whole numbers, and integers. 3. Solve and use proportions. 4. Round numbers to the nearest thousand, hundreds, tens, units, tenths, and hundredths. 5. Solve problems and make applications involving percentages. II. Measurement 6. Select and compute with appropriate standard or metric units to measure length, area, volume, angles, weight, capacity, time, temperature and money. 7. Convert, compare and compute with common units of measure within the same measurement system. 8. Read the scale on a measurement device to the nearest mark and make interpolations where appropriate. III. Geometry 9. Recognize, classify and use characteristics of line and simple two-dimensional figures. 10. Find the perimeters (circumference) and areas of polygons. 11. Find surface areas and volumes of rectangular solids. IV. Data Analysis 12. Read, interpret and use tables, charts, maps and graphs to identify patterns, note trends and draw conclusions. 13. Use elementary notions of probability. 14. Compute averages. V. Algebra 15. Solve simple number sentences and use formulas. 16. Evaluate algebraic expressions.
50% of the entering 9th graders fail this test each year. 40% of the entering Freshmen in community colleges fail a similiar test each year and have to take "developmental math". One Ohio university offer 14 credit hours in this K-8 math, before the students can take "Introduction to Algebra" a 9th grade level class.