Revealing mistake: At World Picture Corp, when John and the guy with the broken clavicle are lowered from the overhead joists they're both wearing lifebelts buckled around their waists. The problem is that once they reach the ground, we can see the additional carabiner attached to John's lifebelt, which is also attached to extra green support protruding from under John's shirt. We can also see the victim's additional carabiner going under his flannel shirt. While Roy is on the line with Rampart, when John removes the victim's lifebelt, the extra carabiner is still protruding from under the victim's shirt and John places his hand over it. (00:27:00)
Revealing mistake: When Station 51 is dispatched to the gas explosion at the cafeteria, during the actual rescue the four firemen we see in closeup in the cafeteria are supposed to be Roy, Johnny, Chet, and Marco, but it's really odd that all are the doubles, very obvious in the closeups. There's little dialogue during this scene, which was dubbed later in ADR.
Revealing mistake: When Station 51 is dispatched to a man trapped at World Picture Corp, just as they reach the entrance to World Picture Corp, the Sheraton-Universal is seen on the corner, and the street sign for touring Universal Studios is visible as well. (00:19:45)
Visible crew/equipment: After winning the semi-finals basketball game against 16, when Captain Stanley, John and Roy walk into the kitchen, Roy and Cap stand near the stove, and two tape marks are visible on the floor.
Visible crew/equipment: At World Picture Corp, after the rescue of the guy with the broken clavicle trapped up on the joists, Morton tells Roy to transport the patient as soon as possible. It cuts to a shot of Squad 51 following the ambulance to ER receiving, and as they drive through the underpass, it's from the POV of inside the squad. Some location lighting becomes visible on the right side, and the reflection of the cameraman's legs are visible on the windshield, as he's seated in the passenger seat. We know that one of the paramedics is in the ambulance, so there should only be a driver in the squad.
Visible crew/equipment: After spending all night on the job, when the tired guys of 51 are at the basketball game, the outlines of the mic transmitters and wires are visible on the backs and sides of 51's jerseys, particularly when Roy gets injured. (00:36:00)
Continuity mistake: During 51's basketball game against 16's, the sweat stains on the guys' clothing keep changing between shots.
Revealing mistake: On the way to the basketball game against 16, when all the guys are pushing Chet's station wagon down the street, it's Kevin Tighe's double who is pushing the car, and he looks nothing like Kevin.
Continuity mistake: During the basketball game against 16, when Chet is finally in The Game at halftime, 51's side of the court is at the right of the screen, but in the closeups of Chet's shot going into the hoop - scoring, we can tell by the wall and backboard that a bunch of his baskets are actually going into the hoop on the other side of the court, behind him.
Continuity mistake: After winning the semi-finals against 16, when Chet walks into the kitchen in the closeups John's holding the newspaper filled with photos on the page facing out, but in the wideshots an entirely different page faces out. (00:45:00)
Continuity mistake: During 51's basketball game against 16, when Chet takes his first shot and makes the basket the scoreboard now shows 51's at 16 and 16's at 30, then Chet makes the second basket, but the scoreboard shows 51's still at 16 and 16's at 32.
Visible crew/equipment: When 51's guys are at their practice game, the gymnast is injured and the outline of the mic transmitter is visible on the back of Johnny's T-shirt. (00:16:40)
Continuity mistake: At start of episode, when Captain Stanley walks in announcing the upcoming game against 16, the paper he's holding changes hands between shots. Then after Cap sits down, the paper again changes hands between shots. Also notice that after Chet finds Henry's bone behind him in the couch, he gives it to Henry then puts it back behind him again, then gives it to Henry once again.
Continuity mistake: When Captain Stanley is writing on the board about the practice game at 9:00 am on Thursday, the board was clean before he started writing, then the board is dirty, and by the time he walks away the board is clean around what Cap just wrote, and his handwriting and its position on the board have changed as well.
Continuity mistake: After winning the semi-finals basketball game, when Chet walks into the kitchen Roy places a glass of milk on the table in front of Chet, which vanishes in Chet's closeups.
Continuity mistake: During the basketball game against 16, after the ref tell John that he can't call timeout unless they have the ball, Marco passes to Mike, who passes it to Johnny. When 16 gets the ball the blonde player with blue wristbands shoots, but in the closeup it's a brunette without wristbands who scores the basket. Plus the fact that in the closeup the basket he scores in is the one on the other side of the court, and the next few closeups of 16 scoring baskets are in the opposing team's basket, on the other side of the court.
Continuity mistake: After Roy injures his ankle, when Captain Stanley tells Chet that he's replacing Roy, John squirts Cap with the water bottle soaking the front of his shorts, but when they get up to resume The Game Captain Stanley's shorts are completely dry.
Answer: I was rewatching a few first season episodes of Charlie's Angels (1976), and in S1xE6 "The Killing Kind," I recognized the same actor. So, to finally fully answer your question, the two baseball players in School Days are played by Rod Perry and Sean Fallon Walsh.
Super Grover ★