Open files using Text Edit by default
Since the file extensions are all different, you will need to batch edit all the file extensions in order to have TextEdit be used as default. Clicking "change all" on one would not work:


Assuming all the files are in the same folder and are text files, you can use a terminal command to batch edit the extensions so TextEdit opens them by default.
To do so, open Terminal and do the following, replacing the /path/to/folder with the folder containing these files:

cd /path/to/folder
for file in *; do mv "$file" "${file}.txt"; done


e.g. "APW.01" becomes "APW.01.txt"

Alternative, cleaner solution: a sequential rename adding .txt to each file.

cd /path/to/folder; i=1;for f in *; do mv "$f" "APW_0$i.txt";let i++; done


Before:



After: