Are these educational apps and websites free, or do they require a subscription?
这些教育应用程序和网站是免费的还是需要订阅？
The availability of free versus subscription-based educational apps and websites varies. Our list includes a mix of both free and paid options, allowing you to choose according to your preferences and budget.
免费与基于订阅的教育应用程序和网站的可用性各不相同。 我们的列表包括免费和付费选项，您可以根据自己的喜好和预算进行选择。