Here's how you can help :
1) Correct the text in the tutorial maps
Since English is not my main language, I might either write my phrases incorrectly or write them funny. You can offer to correct the text of any number of tutorial maps you wish.
2) Create tutorial maps
The obvious one. Create tutorial maps to help complete the tutorial pack.
You pretty much have the following options for this task :
2.1) Make tutorial maps to fit the "newbie training" tutorial maps
2.2) Make stand-alone extra tutorial maps which doesn't fit any standard path of teaching
While the tutorial maps are mostly focused on triggering, you can also submit a tutorial map of any other domain (modeling, cinematics, etc.)
Here's the current plan for the tutorial maps so you can guide yourself for the creation of tutorial maps. So far Chapter 0 and Chapter 1 are considered "complete" but still can accept more tutorial maps.
Chapter 0 (early Object Editor) :
Completed maps
To do
Chapter 1 (Simple Actions) :
Completed maps
To do
Chapter 2 (Events/Conditions) :
Completed maps
To do
Chapter 3 (Variables) :
Completed maps
To do
Chapter 4 (Various such as Leaderboards, Quests, etc.) :
Completed maps
To do
Chapter 5 (Cinematics) :
To do
Chapter 6 (Campaign) :
To do
Chapter 7 (JASS) :
To do
Extra map tutorials :
Completed
Potencial extra tutorials to create
3) Create text tutorials
You can always create the traditional type of tutorials however it is much more preferable to make any tutorial in map form if it is more pratical or logical.
For example, if it's about triggering, it is preferable to make it into a tutorial map instead. However, if it's about a modding tool then it will obviously be better to make it into a text tutorial.
4) Submiting improved versions of any current tutorial content
You are allowed to submit any improved version of anything specific if it is more improved in any sort.
5) Create "Show-off" maps & Sharing modding material
You can create maps to show off in any falshion. It's less about teaching than to show what can be done. This can include any combinaison of domains (triggering, moding, cinematics, etc.)
If you want to submit your models, skins or other modding material in map form to be openly used by others, that also fits in.
6) Find open-source maps
While specific tutorial maps can teach specific aspects in deep precision, a newbie can also learn a lot from opening complete maps and studying them.
If you are author of a map in question, feel free to submit the map directly. Otherwise, if you are someone that found an open-source map, give me the link so I can download the map and contact the map's creator to get his permission to add it in the pack.
7) Spread the word
It might not get your name in the credits but it does help to make this tutorial pack known to more people.
EDIT :

You can suggest tutorials about whatever you want. Since there would be a real need for a specific one, potential tutorial makers will be more tempted to make it.