Keyboard keeps crashing in Cyanogenmod 10.1.3
Here's a few tips for troubleshooting:

Go to System Settings > Apps > click Android keyboard (AOSP). Clear Data. Clear Cache.

If that doesn't work, and you have a custom recovery, reboot into recovery and clear the entire cache, clear davlik cache, and go to advanced > Fix permissions.

Other than that, you could try uninstalling and reinstalling from Google Play or downloading a different keyboard.