You may find you don't even get asked for any games in your first year teaching, but if you do it can be hard at first to come up with anything original, especially when it's not completely clear at what level you should pitch your activities.
These two sheets are examples of the kind of thing teachers want from you.
The first is a sheet where students answer multiple choice questions to pick the right spelling of a word. As 1st graders usually don't have good reading and writing skills, this is potentially difficult. My version is very simple, but if you think they can handle it (or have started learning to read and write in elementary) then make it harder.
Here's the sheet for download.
The next is a fun and simple game testing the order of letters in the alphabet. Students have to uncover the hidden message by working out the letters before the ones on the sheet.
And here's this sheet.