There are a ton of different apps can do parental controls with everything from tracking the phone to locking certain apps with a PIN. I guess it depends on if you want them to be blocked from being downloaded or if you want to be able to use them, but just password protect the apps.
Just search in play store app lock there will be many usefull apps to lock an app with password, also if your device runs lollipop theres a feature that lets you setup different profiles on your phone, so u can set what apps will be available to that profile.
I have a option in my phone in which i create a different profile and customise it with few selected apps and game that i want the kid to play, he cant have access to anything else. That should work for you