Math and Beyond

Okay so I'm trying to figure out how to do this http://themetapicture.com/japanese-math/ with smaller numbers. Here are my own step by step examples. Not going to say they're right but I need to figure out where I am going wrong before I teach it if I am. Can it not be done with single digits without having to count every intersection? There has to be some sort of short cut? These are what I have so far. I'm trying to appeal to those struggling learners. You gotta get creative as a teacher!

Example 1:

 Example 2:

 

Connect the 5 and 3 circles to get 8 on the last one

Any suggestions?