A has an important role in language, its more than just filler. I am not an English expert, but I can look up some grammar to refresh myself a bit.

Which animal, how many eggs, what cat, what hat?

[A] identifies a single, but not specific, person or thing. -Merriam-Webster

“The” has the opposite role.

There is a cat at the pond. The duck quacked at the cat.

In the first sentence, I introduced the existence of a cat. In the second sentence I referred specifically to the cat.

https://www.merriam-webster.com/dictionary/indefinite article

https://www.merriam-webster.com/dictionary/a#dictionary-entry-2

It smooths out the pronunciation when reading out loud.

Here’s some examples.

A farmer fed a animal and got a egg.

A farmer fed an animal and got an egg.

The woman put on a orange hat.

The woman put on an orange hat.

The duck quacked at a cat

The duck quacked at an cat.

The “a orange” could work if you produced a “uh” instead of “eh”. But I think an is the smoothest. “an cat” is just a fun incorrect use of an.

Minecraft has a ton of potential. So many ways to develop creativity, problem solving, redstone, and using commands.

Then there’s modding. navigating the web to find safe ones, navigate the file explorer to put them in the right spot. Troubleshoot mods that don’t work together. (I remember having to manually change hundreds of Item IDs before they changed the system).

5 is probably too young to start with mods, but texture packs would probably go well, open up paint and start scribbling on blocks. Eventually give them paint.net (or anything more complex than Win Paint) and start messing with layers and saving things to the right file type.

Does the kindle fire let you do USB transfer for music and books? Transfer stuff manually. (Amazon taking the download feature away from the store, so books will need to be got elsewhere) I’m a big fan of Standardebooks.org, all free and public domain, not a lot of children’s books, but should be good by the time they’re 10. Although the LCD screen probably isn’t the best for reading, I’d get them an eink for reading time. Also easier to separate reading time from game time. Also if you can go to the public library for physical books. The simple responsibility of borrowing a books, taking care of it and having to return it on time is good. (I’m rambling off topic…)

Install a bunch of easy puzzle games. I’ve always like Flow, there’s also simple math ones, sudoku, jigsaws, word searches, find the object, there’s probably a hundred others.

The tablet is only as detrimental as you make it. Find games with an actual story that the kid has to read. 5 might be a bit young for RTS games, but those will definitely make him read and think. When they get stuck, show them how to find the guide online and read just enough while avoiding story spoilers.