Olá, fiz as aulas e recebi alguns erros no console:
E/SQLiteLog: (20) statement aborts at 8: [UPDATE Alunos SET id=? WHERE id=?] datatype mismatch
D/AndroidRuntime: Shutting down VM
E/AndroidRuntime: FATAL EXCEPTION: main
Process: br.com.alura.agenda, PID: 4630
java.lang.RuntimeException: Unable to resume activity {br.com.alura.agenda/br.com.alura.agenda.ListaAlunosActivity}: android.database.sqlite.SQLiteDatatypeMismatchException: datatype mismatch (code 20)
at android.app.ActivityThread.performResumeActivity(ActivityThread.java:3581)
at android.app.ActivityThread.handleResumeActivity(ActivityThread.java:3621)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2862)
at android.app.ActivityThread.handleRelaunchActivity(ActivityThread.java:4699)
at android.app.ActivityThread.-wrap18(Unknown Source:0)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1595)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6494)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807)
Caused by: android.database.sqlite.SQLiteDatatypeMismatchException: datatype mismatch (code 20)
at android.database.sqlite.SQLiteConnection.nativeExecuteForChangedRowCount(Native Method)
at android.database.sqlite.SQLiteConnection.executeForChangedRowCount(SQLiteConnection.java:735)
at android.database.sqlite.SQLiteSession.executeForChangedRowCount(SQLiteSession.java:754)
at android.database.sqlite.SQLiteStatement.executeUpdateDelete(SQLiteStatement.java:64)
at android.database.sqlite.SQLiteDatabase.executeSql(SQLiteDatabase.java:1754)
at android.database.sqlite.SQLiteDatabase.execSQL(SQLiteDatabase.java:1732)
at br.com.alura.agenda.dao.AlunoDAO$override.onUpgrade(AlunoDAO.java:71)
at br.com.alura.agenda.dao.AlunoDAO$override.access$dispatch(Unknown Source:68)
at br.com.alura.agenda.dao.AlunoDAO.onUpgrade(AlunoDAO.java:0)
at android.database.sqlite.SQLiteOpenHelper.getDatabaseLocked(SQLiteOpenHelper.java:338)
at android.database.sqlite.SQLiteOpenHelper.getReadableDatabase(SQLiteOpenHelper.java:262)
at br.com.alura.agenda.dao.AlunoDAO$override.buscaAlunos(AlunoDAO.java:104)
at br.com.alura.agenda.dao.AlunoDAO$override.access$dispatch(Unknown Source:107)
at br.com.alura.agenda.dao.AlunoDAO.buscaAlunos(AlunoDAO.java:0)
at br.com.alura.agenda.ListaAlunosActivity.carregaLista(ListaAlunosActivity.java:62)
at br.com.alura.agenda.ListaAlunosActivity.onResume(ListaAlunosActivity.java:75)
at android.app.Instrumentation.callActivityOnResume(Instrumentation.java:1355)
at android.app.Activity.performResume(Activity.java:7107)
at android.app.ActivityThread.performResumeActivity(ActivityThread.java:3556)
at android.app.ActivityThread.handleResumeActivity(ActivityThread.java:3621)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2862)
at android.app.ActivityThread.handleRelaunchActivity(ActivityThread.java:4699)
at android.app.ActivityThread.-wrap18(Unknown Source:0)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1595)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6494)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807)
Por conta do número de caracteres vou colocar os códigos nas respostas, mas se alguém já souber o problema, fico grato!