The order of teaching math topics in sixth grade may vary depending on the curriculum and teaching method used, but in general, a good starting point for teaching math in sixth grade would be:

1. Basic operations (addition, subtraction, multiplication, division) with integers, fractions, and decimals
2. Place value and number sense up to 10^9
3. Ratios, Proportions and percents
4. Basic algebraic concepts (including solving equations and graphing linear equations)
5. Geometry and measurement (including perimeter, area, volume, and angle measures)
6. Data analysis and probability (including mean, median, mode, range, and probability)
7. Basic geometry concepts (points, lines, planes, and symmetry)
8. Rounding and estimation
9. Basic concepts of geometry in 2D and 3D, including symmetry and transformations.
10. Basic concepts of statistics and data analysis.
11. Basic concepts of scientific notation
12. Basic concepts of exponents and scientific notation
13. Basic concepts of square roots and basic concepts of geometry(surface area and volume)
14. Basic concepts of ratios, rates, and unit rates
15. Basic concepts of proportional reasoning
16. Basic concepts of absolute value and integers
17. Basic concepts of prime factorization
18. Problem-solving and reasoning
19. Graphing and data interpretation
20. Mental Maths
21. Basic concepts of geometry and measurement conversions