I tutor several children with math struggles. One 16 year old can do addition with a number line. In my opinion a number line teaches people that math is hard when used beyond showing why math works. This is slow and he makes a lot of mistakes. He is working on multiplication. As he learns multiplication he forgets his addition facts. Math does not seem to connect to itself. Good multiplication often builds on good addition. For him each fact seems to stand alone.
We are playing a war or battle game with cards. Each face card and the 10 are worth 10 points. The numbers are worth their number. Instead of playing one card, we play two and the total of the two is compared to the other players two cards. The highest number wins. This works well because he can count the hearts or spades on the smaller cards and he is learning to add while playing.
If someone with reading problems is struggling with math, a tutor needs to check to see if it is word problems causing the confusion. If it is word problems, reading may be the problem. If reading is the problem read the problem aloud to the student to build math confidence as you work to raise the reading level. As a learner reads better have him read the word problems aloud to you instead of you reading to him. As he gets more confidence have him read part and you read part and then as he reads better have him read to himself while you listen and encourage and help with any words so he does not stumble and lose the meaning of what he is reading.