I just uploaded a 12-Week Middle School Training Plan to the Coaching Distance Store. As with all store items, it's free to D-Crew Members.
I work as an Elementary Physical Education teacher, a High School Cross Country and Track Coach and then also coach middle school runners in the summer, so I've been able to see logical connections from one developmental level to another.
The middle school training plans are designed to be the first "taste" of training for kids; enough to help them see growth and link 8th graders to 9th grade high school training.
I like the idea of fartlek training for middle school kids, as you could literally do this on a a track. All you need is a bunch of wild junior high kids and a whistle. The other concept I've learned works better for younger kids are off-distance time trials rather than repetition or interval training. There's plenty of time to bore kids with that later.
Speed (like 5 seconds or less) is also a foundational component of these plans, along with daily pre and post run work that doesn't need any equipment and includes video instruction.
Like the high school plans, there is a step-by-step approach to increasing training volume.
If you're a middle school coach, I think this will make your life easier.
As always, the Training Plans are free for D-Crew Members and just 29.99 for the civilians.