zOur prophet Muhammad, peace be upon him, taught us a beautiful supplication (dua) to make after the adhan.
Learn it and teach it to the believers.

After hearing the adhan (prayer call), we say;

"Allahumma Rabba hathihid-Daawatit tammah, wassalatil Qa imah ati Muhammadan al waseelata wal fadeelah, wab aathu maqaman mahmoodan allathee wa aadth, innaka laa tukhliful-me'aad."

And it means: :

"O Allah, Owner of this perfect call and Owner of this prayer to be performed, bestow upon Muhammad al waseelah (a station in Paradise) and al fadeelah (a rank above the rest of creation) and send him upon a raised platform which you have promised him. Verily, You never fail in Your Promise."

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