Trying to download, Weather Bug App? Tablet says it's Downloading?

if that what it says then that is why it is not downloading
get a version of the app that is compatible with the tablet

Mostly It's Just a Bug or a issue with the Play Store itself... I Would Advise Restoring your Device From Scratch or Updating to the latest software.

Tablet Reset

download games

Make sure you go to security settings or advanced settings and accept security certificates of non microsoft programs and accept cookies from from inverified sources. This should help. Also make sure that you ad the program or website to your firewall exception list. Hope thus helps.

Im guessing that the app/game was corrupt or incompatible with your tablet. You will have to reset your tablet to factory settings and restore your apps and other items from google, if you had it set up for this. To do a reset go to settings - about tablet - reset - factory. Then let it restart.

Might be your tablet not supported to that app or possibly it should not be a appropriate application :
So download this app from play store
Battery Doctor(Battery Saver)

and if this fails
possibly problem in you tablet software go to replace it .....

Have you ensured the download of the games has completed downloading, it can take awhile, check the icons in the tablet, check, if the download was interupted or stopped or your device was turned off, try downloading again, go to the app just prior before purchase, it should say a status like (downloading or in progress) if there is definately no processing or installing talking place at all, try turning off the device completely and see if it configures , i will answer and help you through this , i will reply promptly, but first what tablet do you have? model or version number.

The OS is Android. Try this and see if it works, I had a android phone that gave me the same error a few times.
settings/app manager/googleplaystore/clear cache