It's good that you're catching it quickly. I would strongly recommend the Huntington Learning centers. We sent our 18 year old nephew there. Yes 18. He'd successfully graduated from high school yet wanted to go to college and didn't have the skills. They made up a specific plan, got him caught up in almost 5 months, and he's finishing soon. Next he's going to study for the SATs. Yes, they are more on the pricey side, but they do an evaluation and it's all PRIVATE! My kids are doing well in school and yet over the summer I plan on sending them there for a couple of weeks just to review how they are doing comparatively to other kids their age and to prep them for the next grade. Even though I do a lot of math with them at home as well. I still think it's worth it.
The changes in my nephew are phenomenal. Not just in his abilities, but in his speaking skills and his confidence. I'm so happy we did this for him
Even if you can't afford the program for however long they recommend, it's still worth it to get an evaluation in case any thing is wrong or to feel that peace of mind that there isnt anything wrong.
Good luck,
S.
ps. I wanted to add that I agree with the parents here who encourage you to escalate it up the chain of command. Ask to speak with the principal and the counselor. This is not your burden alone. Schools voice the idea that education is team work, so hold them to it. If that fails consider huntington.