Question

After we did two types of sand together, he did the rest on his own.
or
After we had done two types of sand together, he did the rest on his own.
Which one is correct?

Answer 1

The second (although I don't know what "had done two types of sand" means) because of the rules of sequence of tenses.

Answer 2

thank you this is the whole paragraph
I helped a student with his sand lab because he did not have a partner. I helped him find different objects in the sand. I also showed him that switch the magnification will show different images. After we had done two types of sand together, he did the rest on his own. He would call me over to show me the items he found in his sand.
If you could look over this thank you