What are the tackling, bounce, marking and kicking rules from Under 13 up?

From Under 13/14 through to Under 16/17/18 (Junior Rules Handbook):

• Tackling and contact: full tackling and bumping, fending off, smothering, barging and stealing the ball are all allowed.
• Bounces: unlimited.
• Kicking off the ground: permitted.
• Marking: a direct catch of a kick that travels 15 metres.

Mouthguards are strongly recommended at all levels of football, and a custom made one gives the best protection (a boil and bite one is better than none).