The reading intervention that you would need next is for fluency. I would suggest Read Naturally, or, even better (though less familiar to schools), HELPS (http://www.helpsprogram.org/). HELPS has the advantage of being very low cost, and fairly easy to implement (easy enough that you could do it yourself, or hire a responsible college student to do it). It also has a respectable research base.

...pronounced like the long vowel and first letter of the alphabet...