A rounded, solid wooden or hollow aluminum bat. Wooden bats are traditionally made from ash wood, though maple and bamboo is also sometimes used. Aluminum bats are not permitted in professional leagues, but are frequently used in amateur leagues. Composite bats are also available, essentially wooden bats with a metal rod inside. Bamboo bats are also becoming popular.

Helmet worn by batter to protect the head and the ear facing the pitcher from the ball. Professional models have only one ear protector (left ear for right-handed batters, right ear for lefties), amateur and junior helmets usually have ear protectors on both sides, for better protection from loose balls, and to reduce costs to teams (all players can use the same style of helmet).
This is the drill we ran all through high school. It is the most time effective and skill intensive way to warm up a team, but your boys must be able to play catch! Fungo-ers stand in the "fungoe circles" that any good field has (and if it doesn't, you know where they're supposed to be - just outside of the home-plate dirt circle, towards the dugouts). The catch to this method is this - you have two first basemen, allowing both sides of the infield to throw across. Herein lies the only danger - one of the firstbasemen has a lengthy throw back to a shagger, so caution must be excersized (a catcher with a good head on his shoulders really helps).
Maple bats in particular were once known (circa 2008) to potentially shatter in a way that resulted in many sharp edges, sometimes creating more dangerous projectiles when a bat broke.[9][13] Maple bat manufacture evolved significantly, in cooperation with Major League Baseball,[11] paying special attention to grain slope, and including an ink spot test to confirm safest wood grain orientation.[11]
First base fungo hits fly balls to center field (helps here if both fungo hitters move up and apart, hitting from about the front of the mound extended towards the bases). Center throws to second, second baseman is cutoff (for us it was, anyways - change to suit your style). Third base fungo hits balls to left field, who throw to third, with a second shortstop as cutoff (but you really don't need one, if you're shorthanded).
To practice throwing around the infield, Bates recommends several drills you can use. The first involves placing four fielders in a square, about 15 feet apart. The players flip the ball underhanded to each other, like in a double play. Keep their arms straight, using a stiff wrist, with gloves on their hips once the ball is out. Every fielder follows their flip, glove side first, rotating around the square. The idea is to have a sequence of catch, flip and follow. The ball should be caught with two hands, palms open. After about two minutes, repeat the process rotating the other way for another two minutes.
Players can also create complex holes such as ‘two-part holes’ where the players must hit or reach one object before attempting to shoot at the hole. For example, a ‘two-part hole’ could consist of hitting the scoreboard first, and then once they have hit the scoreboard they must hit the ball back to home plate, that would be one hole with the player with the fewest strokes winning the hole. ‘Two-part holes’ are typically saved for the last hole in order to make things more complex and difficult on the leader.