American Sign Language University makes their Lifeprint curriculum lessons available free online. These can be used with all ages. (Adults can also sign up and pay for courses to receive credit.)
Asian Language School offers both live and pre-recorded courses for Japanese, Korean, or Chinese languages with seperate courses for students in the elementary grades and for teens.
Native Spanish-speakers base in Antigua, Guatemala teach Spanish to individual students (or two students) via Skype. While following a curriculum, programs will be planned for the appropriate level for each student.
The Wierman Study Center offers self-paced, online video lessons for ASL via monthly subscriptions. Students get personal feedback on homework assignments.
free grammar texts and readers for Greek and Latin
Jenny, the author of the Hobby Helps blog, has a lengthy post with tips for learning Spanish quickly for both adults and children. She includes practical suggestions, recommended resources, and weblinks.
Never having studied Chinese, I am unable to review products specifically for that language. But, because I know that many families want their children to learn Chinese, I want to alert you to sites that have been recommended to me. BetterChinese.com has resources for teaching Chinese to all ages. LingoBus.com and YoYo Chinese on You Tube are two other sources that have been recommended to me.
Begin to learn Japanese online with free introductory lessons. Subscribe to continue with advanced lessons. Lessons are multi-sensory.
Note: Publishers, authors, and service providers never pay to be reviewed. They do provide free review copies or online access to programs for review purposes.
Disclosure of Material Connection: Some of the links in the post above are "affiliate links." This means if you click on the link and purchase the item, I will receive an affiliate commission. Regardless, I only recommend products or services that I believe will add value to my readers. I am disclosing this in accordance with the Federal Trade Commission's 16 CFR, Part 255 "Guidelines Concerning the Use of Endorsements and Testimonials in Advertising."