In my experience teaching Math to grade 6 and 7 students, I have found that incorporating Scratch (https://scratch.mit.edu/) has helped solidify most students understanding of x y axis and coordinates. If you’ve never used Scratch before, it’s a free, on-line programming software that allows you to program and code animations and games. Scratch uses a coordinate system, which determines where you place sprites and which directions you want them to move. Each sprite has two values to locate its reference point. The students I have worked with quickly pick up how the x-y axis works. As an educator, you can set up student accounts to see their work and help share it on their digital portfolios. It’s also a way for students to share evidence of their learning in math. This is a youtube video to show you the basics:
Scratch Ed (http://scratched.gse.harvard.edu/) is a site dedicated to educators. You can exchange resources, share ideas, and ask questions.