Furyu released the official NEW GAME! Nintendo 3DS themes based on the TV animation from the previous season. Each of them costs 200 Yen (with tax) but you can buy both of them in one package price for 300 Yen (with tax).
The first theme comes with the main visual of the anime while the 2nd one is an 8bit style version of the main characters and Mozuku the cat of Hazuki-san.
Both of them comes with normal wallpapers on the top screen and moving ones on the bottom screen with sound effects but with different BGMS! (みんなでお仕事 and みんなで出発). In the gallery you can find the sample pictures.