The debate has been long and emotional for USA Hockey.  Their decision to adjust the rule was related to both safety and player development issues. 

Interestingly, their study was motivated by the observation that once a player reached the pee-wee level and was allowed to check, the player became overly-focused on checking and failed to make the best hockey play in the given situation.  That changed the game for participants, making it less fun for some players.

Like football tackling, hockey checking is as much about protecting yourself as it is stopping the progress of your opponent.  

Consider these teaching points, which are core instruction points within the youth hockey world (for checking) and the youth football world (for tackling).

1.  Always have a good, deep knee bend prior to contact.

2.  Maintain a wide base

3.  Keep your elbows at your side.

4.  Generate your power from your legs and hips, not upper body and arms.

5.  Before contact, be sure to narrow the gap (distance) between the player and opponent.

Do not lunge or leap at your opponent. 

6.  Do not go straight at opponent, rather angle toward where the opponent is heading.

7.  Keep your head up, never duck your head.

In sum, football tackling and hockey checking have many parallels.  Football instruction is an excellent way for young athletes to master the body contact and protection techniques necessary for many team sports, including hockey.