What is a good general Teaching Series for the following

For younger students, I’m using Gogo Loves English.
For a number of years I was using English Travels, but his cycle, I’m having trouble having the kids relate to Book 4 lessons 7 and 8 about technoogy and robots. .
The material just doesn’t click.
I’ve used Gateway Gold but I’m worried about the material . Please recomend a good gernal learning series. I’m thinking about take the kids from English Travels and putting them in Gateway Gold level 2 because this book has a solid gramar foundation.
I live in rural Taiwan and don’t get to the books stores often to check out new offerings.
I find the students get lazy about grammar.
A number of my favorite and still relatively timeless series have stopped being published.
I loved See Saw and I loved the Jump grammar series. But with out these staples, I’m a little lost.

What’s your favorite book. If you are familliar with English Travels, what’s your opion of Book 5. What series would you migrate them into from book 4 that would allow them to refresh their language skills.