From the gardening educators’ list:

Captain Planet Foundation Learning from Home Resources (all ages )  Captain Planet Foundation has recommended resources related to outdoor exploration, STEm and food for learning at home. Filter by grade band, topic, and type of activity.
In Defense of Food Curriculum (Grades 6-8; 13+)
This curriculum from PBS is designed to help adolescents learn why it is important to eat healthfully, investigate how food companies influence their food choices, and create action plans for changing their eating habits.  Virtual Junior Master Gardeners on-line live lessons and activities starting April 2nd
FoodCorps Resources:
COVID-19 Resources page to support educators, parents, school nutrition professionals and others interested. On that page you’ll find a link to this  FoodCorps Resources To Support Remote Education document.  This document includes 35 food and garden-focused FoodCorps Lessons that can easily be adapted to lead in a home kitchen or backyard garden. The lessons are aimed for Kindergarten- 5th grade. They are a part of our suite of nearly 100 FoodCorps lessons that are currently being revised and updated,  which will be posted on our website this summer.
Sprout Scouts Club Handbook on our standard resources page, which includes hands-on activities for elementary aged kids that focus on growing, preparing and eating healthy good (developed in partnership with Life Lab!)