We are accustomed to using the length and/or number of sessions as our measure of how much a child is practicing, but research suggests that we should be paying at least as much attention to the number and accuracy of responses.
For decades methods with strong quantitative and scientific bases, such as such as applied behavior analysis and precision teaching, have measured practice in terms of responses and response accuracy. We aren't as used to doing this in language-literacy treatment, in part, because it can be difficult and/or impractical to monitor the number and accuracy of responses during reading skills practice. Computer-assisted methods make this kind of data tracking practical and even easy.
Lexercise requires sustained attention and taxes working memory. For this reason, some children can only tolerate a minute or two of Lexercise practice at a time. Older students may be able to sustain practice for 15 or even 20 minutes. This is not surprising. We see the same thing in clinics and classrooms.
The goal should be to build the child's tolerance for sustained attention and motivated, accurate practice to at least 10 to 15 minutes. If the child can only sustain attention for a few minutes at a time consider a practice schedule with a few games in the morning and a few more games later in the day. Such "distributed practice" is a well proven schedule for optimal skill-building.
The default setting for the Lexercise games is 5 min. per game, but you can set a game for as short a time a 1 min. My goal for each of my clients is ~ 10-15 min. of "in the zone" daily practice, five days a week. If I can't get that, I drop back to a session length at which I can get "in the zone" practice. I currently have clients working on Practice Plans that range from 3 min. to 20 minutes per day, 5 days a week.
We have heard "practice makes perfect" and "practice make permanent," as well as "perfect practice makes perfect," but research suggests the aphorism should be:
"Motivated, daily practice with feedback makes permanent."
Both quantitatively and qualitatively, a few minutes of practice "In the zone" can be worth an hour or more of "zoned-out" practice.