Giving names of few useful applications relating to animation software programs is not the ultimate solution. You must understand something else as well. It is always a good idea to compare multiple apps that serve a given instructional purpose. I will advise against simply selecting the first app or the most popular app as you, or your students, have specific needs and your app needs will be unique to your circumstances.
Here are few useful animation software programmes:
1. FlipaClip
2. Adobe Spark
3. Animation Desk Classic
4. PicsArt Animator
5. Animoto Video Maker
Besides if you do have any questions give me a call: https://clarity.fm/joy-brotonath