No defense is too hard for players (young and old) to learn. All of the difficulty relies on the ability to teach it. A lot of coaches have a scheme or gameplan that proves to be more than they truely can grasp. A 3-5 would be close to suiside in my opinion. At the 8 - 9 year old level most teams will run 90% of the time. The 3-5 front will not put enough defenders in the box. If you have 5 kids that are exceptional lb's let me come and join your staff ;) But seriously 3-5-3 vs two te's and a wedge will let the opposing team drive the length of the field 3 yards at a time and keep your "O" on the sideline.

Great answer!!!!! Just play a 5-3 and wided the alignments of the de's

I think this really depends on your approach to the roles of the "5" and their ability to engage at the line of scrimmage and attack points. While I agree with the above, my 7-8-9 year olds did fine this year by going with less up front and letting our speed players track the ball down. What we faced were players on the offensive line who did not react well to not having someone head up on them. Gave us quite an advantage in shutting down sweeps. We went 4-5 rather than 3-5 but it worked. We also incorporated a 6-2 as well.

I agree with James. Move the "5" up as ends or OLB. Attack and content the end of the line. Our team went undefeated with the 5-3.
6,7 & 8 yr olds.

I am a Big fan of the 3-5-3 my group of boys(7,8 & 9) went 7 - 0 - 1 (0 - 0) and won Bostons 3rd Annual Baby Bowl...(oh yeah we only gave up 1 TD during the regular season). You definately need 5 fast,smart & aggressive linbackers in order to run this, which I had....at this age most teams just want to sweep and get to the outside, forgetting about the middle which leaves them 1 dimensional actually half of that since there arent many pass plays at that age. The 3-5-3 combined with stunts,twist and blitzes....Im willing to share some ideas as long as i can get some back as well!

That depends on what you mean by a 3-5-3? I'll assume you plan on putting three defensive down lineman and try to allign 5 linebackers? Don't think of it as a "Defense" however put a scheme toghether. In my opinion, to many resposibilities for your backers as they will no have time to read as they should with your front.As James said, put 8 in the box as the opponents will run 90 to 95% of the time. Now, with a five man front and three backers you have 8 and hopefully 9 provided your safety is an alley player and loves to hit.One of three things will happen if they pass. They will complete it, it will be incomplete or it will be intercepted. Thats 1 out of 3 two of which are in your favor. 66% to 33%, not bad odds. Odd man front gives an edge to the O line but hopefully you can over come that with 3 great backers with a little speed. Not sure if this helps.