Block, whose late father Ken built up a huge following for his viral Gymkhana videos, will make her single-seater debut with the ART Grand Prix team as the all-female series forges closer ties with F1.
All 10 F1 teams will have a nominated driver in F1 Academy running in its colours in 2024, with Block becoming the second driver to be linked to an F1 outfit.
McLaren announced that Bianca Bustamante would join its driver development programme for her second year, switching from Prema to ART.
Block said: "I am so excited to be joining the Williams Driver Academy and competing in F1 Academy in 2024!
"This is something I never could have dreamed of. I can’t wait to embrace this new experience and learn as much as possible."
Block began competing in national level rallying in 2021, and won the Open Two-Wheel Drive class in the American Rally Association Championship.
She has also contested four rounds of the Extreme E championship alongside Timo Scheider for Carl Cox Motorsport, claiming a best result of fifth in Sardinia, and entered the US-based Nitrocross NEXT series.
Williams F1 team boss James Vowles added: "We are excited to welcome Lia to Williams Racing as our F1 Academy driver for 2024.
"Lia has already achieved a tremendous amount in motorsport, has incredible natural talent, and the champion mindset and dedication to make a success of her journey into open-wheel racing. We cannot wait to get started on this journey together.
"As a team, we are committed to Formula 1 and F1 Academy’s joint efforts to improve female representation in motorsport, and we look forward to working with Lia as a key part of the Williams Racing Driver Academy."
Block joins Indy NXT racer and three-time W Series champion Jamie Chadwick as a second female member of the Driver Academy.
It also features Zak O'Sullivan, who will make his FP1 debut for Williams at the Abu Dhabi Grand Prix and step up to Formula 2 with ART next year and Franco Colapinto, who will also graduate to F2 with MP Motorsport, as well as Formula 3 racers Luke Browning, and Oliver Gray.
Inaugural F1 Academy champion Marta Garcia will graduate to the Formula Regional European Championship by Alpine series having been awarded a fully-funded seat with Prema.
