Evaluation included velocity, arm action, body type, command, and body language among other points. The list was announced Friday. The Area Code Games came to a conclusion on Wednesday.
A total of 35 pitchers were named to the list of prospects. Harvard-Westlake senior Lucas Giolito, who committed to UCLA, topped the list.
Avis, who was named one of two "Jose Bautista 'Beastmode' Award winners early in the competition, topped out at 94 miles an hour.
Avis, who pitched for the Oakland A's during competition, earned his award after pitching the A's to an 8-0 victory over the Washington Nationals at Blair Field in Long Beach.
Palo Alto High's B.J. Boyd also played for the A's. Boyd and Avis were named to the team following a tryout at Banner Island Park in Stockton, home of the Class A Ports.
Avis was the hardest throwing pitcher at the tryouts, topping 90 consistently.
Avis also threw an 84 MPH slider and used a 75 MPH curve to freeze a batter for a called third strike.
"I was rushing a little bit warming up because like a lot of guys, I was nervous," Avis told ESPNRise. "A couple of the coaches came up to me and told me to slow down my delivery. I did and I think that helped my velocity."
Avis, who verbally committed to Stanford shortly after the A's tryout July 6, pitched two innings allowing one hit while striking out three of the six batters he faced.
"I felt great out there," he said. "I was loose with a little bit of butterflies, but that's to be expected in an event like this. I wanted to concentrate on throwing strikes because in these things you never want to throw balls. Also, it was important for me to mix my speeds because in a showcase like this guys can hit the fastball."
Avis went 10-1 with a 2.39 ERA and hit .459 as a junior to help the Knights win their second straight Central Coast Section title.
He was named to CalHiSports.com first team All-State Underclass honors.
"Freddy did give Stanford a verbal commitment in July and plans on accepting a scholarship and signing a letter of intent with the Cardinal in November," Menlo School baseball coach Craig Schoof confirmed in an e-mail. "Freddy will be the seventh Menlo alum to play for the Cardinal during my tenure as coach (Dave Cornell, Jimmy Noreiga, Ryan Seawell, Kenny Diekroeger, Danny Diekroeger, Jack Mosbacher).