No, the 16-17 Saver Railcard cannot be used to get a discount on Eurostar tickets. This specific railcard is designed for use on the National Rail network within Great Britain (England, Scotland, and Wales). While it offers a fantastic 50% discount on most domestic UK fares, it does not apply to international services or travel between the UK and mainland Europe. Eurostar operates as a separate commercial entity and does not participate in the standard National Railcard schemes. However, young travelers aren't entirely out of luck; Eurostar offers its own "Youth" fare for anyone under the age of 26. These fares are discounted compared to standard adult tickets and can be quite affordable if booked well in advance. Additionally, if you have an Interrail or Eurail pass, you can book a "pass-holder fare" on Eurostar for a flat fee (usually around €30 for Standard or €38 for Standard Premier), which is often the most cost-effective way for young people to cross the Channel if they are doing a larger European tour.