Mathnasium etc versus Online math tools

We have used Beast Academy/Art of Problem Solving for the past two years for Math. My kids are entering 6th and 4th. The company does offer local in-person classes and live online classes, but we have exclusively used the asynchronous mode because it gives me the flexiblity to have them use it when we have time for math. We attempt to do the recommended 30 minutes a day, but some days it's a hour and some days it's none at all. I do know they offer summer school in the area too. 

In particular, I've liked it better than other online math programs I've tried because of the reports and sequencing. For example, you can open up all the lessons and let them skip around, or you can force them into a particular learning stream where they have to pass each lesson in order to continue. There are also in-between options where they can start lessons in any order, but cannot jump to a whole different math topic. Also, it sends me very specific reports via email if they are struggling in a particular area. Example: "kid name" is having trouble with Lesson 3.6 Foundations of Long Division... and then it sends instructions on what exactly my kid is doing wrong in the problem and how to help them. There are also physical books in graphic novel format which are included that describe the math, and online videos and readings. 

Both of my kids have improved their math grades to the point that if we have them do the beast academy on the same topics as their school chapters they are coming home with perfect test scores. Feel free to message me if you want more info, but I have no complaints other than I wish there was a beast academy version for their spelling tests! 

Also a huge fan of Beast Academy - we do the synchronous classes with a live instructor.  They go much deeper into the concepts than school math. It does require homework though.

I wanted to second the previous poster as regards AoPS/Beast Academy. Beast Academy is the best $100 I have ever spent. I have paid more than that in total, buying both the paper and the online format for multiple kids over several years. My kids and I both prefer the online format because it also has great videos, and because no one needs to check problem answers. Beast Academy ends with 5th grade material unfortunately, but I can imagine a 6th or 7th grader benefiting a lot from their harder problems, and from the review.  Beast Academy is school curriculum aligned, but it has creative problems, and is not necessarily the best for rote skills, like learning multiplication facts. An app like Kahoot! might be better for that.

The AoPS format for grades 6 and up is not something I would strongly recommend, however. My older kid has been enrolled in AoPS classes, and will likely continue, but these are expensive, and their textbook format is not at all attractive. The games, and many of the videos, end with Beast Academy, for an (advanced) grade 5 student. Many of the AoPS problems for the older grades are available for free on their alcumus website. 

As regards the online stuff you have already tried: I'm also a fan of Khan Academy, and Dreambox. Dreambox is very limited, even though it has some very creative applications, like Algebra 5+ (meaning an introduction to algebra for 5 year olds that actually works!). Khan academy is free and covers a ton of courses across the curriculum at a basic level. I love it for this reason. It is significantly easier than Beast Academy/AoPS. When my older kid trips up on an AoPS class, they go to Khan Academy for a clearer, more basic, explanation.  

That said, all kids, and especially kids with any kind of learning difference, likely benefit more from in person than from online activities. We visited mathnasium, and got their very useful free evaluation. It felt geared towards weaker students in the lower grades. At the center we visited no kids were doing Algebra I or above. My kids loved it and wanted to go back, because there were prizes and easy worksheets, but I wasn't sold, especially since their pricing is around $400 per month (for up to 10 sessions.) 

Firecracker Math, Russian School of Mathematics, Academic Talent Development Program, and Berkeley Math Circle are other in person options perhaps worth exploring.