A few math thoughts.
1. Curriculum hopping can make for big issues in math. Do your research (aka. find samples online and spend a few weeks having the child do them, actually take and follow the placement test guidance, etc). Then stick with a company’s math and slow down or supplement with extra practice ideas where needed. It is not a race.
Our history – oldest did 3 years of Saxon in K, 1, 2. We set it aside in 3rd grade and started completely over with the first level (Alpha) of Math U See. Then we stuck it out for Alpha through Algebra 2, until the last 2 years of high school, where she chose to do a year of Consumer Math from Abeka (really old textbook) and a year of working on weak areas as ACT prep using CTC Math Online (didn’t love it for some of the upper levels, but as a senior, she just needed something to do).
The other kids have used Math U See. Last year while oldest used CTC math I had my then 7th and 8th graders use CTC Math too. It was ok, I wanted them to have one more year to solidify math skills before tackling Algebra 1, so anything would work. This year they are happily back to Math U See and moving through Algebra 1 just fine. The rest of the kids have only use MUS and I don’t foresee them using CTC math at all.
We did have most of the Life of Fred series years ago but my kids didn’t like it.
2. Next thought to share: keep one main curriculum and when you have a child stuck on a concept do 2 things. First, try presenting it a different way (look online for free ideas/websites/worksheets/videos). Second, move into a different math concept for a while and review the stuck area once a week. Kids ‘math brains’ are all different. One will find a certain type of problem easy but struggle with a different type. Others will be the opposite. (Ex: Spatial/3d/Geometry may make sense to them while they struggle with simplifying equations that need factoring, while another child can simplify and factor easily but can’t grasp geometry concepts quickly.)
3. Have them narrate their math process. Sit with them and see what they are doing/thinking/how they progress through a page of math work. You said they were taking longer on a page so you switched. Taking longer can be a matter of not having basic facts mastered so they get bogged down by multi-step problems that require multiple smaller problems to be solved along the way (ex: a 5 digit division problem becomes difficult when you struggle to remember basic division facts – stop and master those!). It can be a matter of difficulty remembering the order of operations or the steps to solving a multistep problem (can you give them a written page with formulas and step by step guides?). It can be a matter of the child being distracted by sounds, smells, things they see, daydreaming, etc. I have one son who will suddenly comment on conversations happening in an adjoining room between siblings while doing math. He has to wear noise cancelling headphones like you would wear at a shooting range to stay focused on math. Taking longer can also simply be a matter of a curriculum having too much assigned – instead of crossing off problems, only assign one side of the page, or one or two sections of the worksheet today and the next two sections tomorrow. Or it can be natural – math increases in difficulty the older you get.
I think so many people get stuck thinking Charlotte Mason promoted short lessons and forget that as a student gets older their lesson length naturally increased in most subjects. In other words, ‘short’ lessons for a 2nd grader are not the same amount of time as ‘short’ lessons for a 5th, 8th, or 11th grader. And in the end, the lessons are not ‘short’, they are focused and longer quite naturally as the child progresses to more mature ages. Math would be an area a child spends more time in as they get older, while something like picture study would not take more time.
