If text is very long I look for ways to break up the reading by having student draw something in a box I have added to the text.
In the first picture we were reading about characteristics of hurricanes, blizzards, thunderstorms and tornadoes. I created boxes while I was typing the information and gave students a few minutes to draw a scene that featured some characteristic of that type of severe weather. I was rigid about the time frame. If the student was not done they would have to finish later. Students also were required to color the pictures in but most had to finish during their free time. Their right hand assignment was to complete a venn diagram comparing and contrasting two of the four severe weathers discussed.
In the second picture we were discussing how clouds were formed and the three types of clouds. The drawings in the boxes was their notebook activity for the day (we also watched a film about it so I had very limited time to work in the notebooks). On the first page students drew the steps of how clouds formed (using the text above as guidance) and on the second page students drew and labeled the three basic cloud "shapes."
Students like the read/do model since it does require them to engage in the text a bit more then just reading and highlighting.