What do you think is going to be the most challenging part of Alg.1 and why?

Explanation:

When I took algebra I, the most difficult part for me was inequalities.

I had been used to linear equations and even quadratic equations, where the operative rule is "keep the equal sign sacred" (whatever you do to one side must also be done to the other side). Once I figured out that multiplying or dividing inequalities by a negative number reverses the comparison, I was good to go.

__

These days, algebra I also includes a good dose of statistics. That seems to trip up a number of people, including me. The main thing, I think, is to stay clear on the definitions, and whether you're talking about a population or a sample. A lot of the math is easily handled by a graphing calculator or spreadsheet, so familiarity with the use of those is a great bonus (almost required).

__

You will be better equipped to go into algebra I if you have memorized multiplication tables, rules of divisibility, some mental math procedures, and squares and cubes of small integers (square ≤ 20^2, cubes ≤ 10^3). This will help immensely when it comes to factoring. Similarly, you need to be familiar with arithmetic involving decimals, fractions, and mixed numbers. Numbers in one form should offer you no more challenge than numbers in any other form.

__

A big challenge for many people is the fact that math builds on previous learning. If you don't learn the early stuff well, and practice it a lot, then you will find you have difficulty drawing on that knowledge to make the later stuff easier. It's NOT a "test and forget" sort of deal. It's a "remember this forever" sort of deal.