UPDATE : Allowing to select a height range for spawning

impulse/Assets/Scenes/MainScene.unity

@@ -584,6 +584,7 @@ MonoBehaviour:
   m_Name: 
   m_EditorClassIdentifier: 
   gearPrefab: {fileID: 7134382842353009887, guid: bfde8172a222719488e32620f57841ca, type: 3}
+  spawningHeightRange: 0.7
 --- !u!1 &1099179302
 GameObject:
   m_ObjectHideFlags: 0

impulse/Assets/Scripts/Road/CollectibleGenerator.cs

@@ -6,6 +6,8 @@ public class CollectibleGenerator : MonoBehaviour
 {
 
     public GameObject gearPrefab;
+    [Range(0, 1f)]
+    public float spawningHeightRange = .5f;
 
     public void SpawnCollectibles()
     {
@@ -26,7 +28,13 @@ public class CollectibleGenerator : MonoBehaviour
             if (spawnSlots.Count > 0)
             {
                 int randomIndex = Random.Range(0, spawnSlots.Count);
-                Instantiate(gearPrefab, spawnSlots[randomIndex].position, Quaternion.identity);
+                Transform chosenSlot = spawnSlots[randomIndex];
+
+                float randomHeight = Random.Range(0, spawningHeightRange);
+                Vector3 spawnPosition = new Vector3(chosenSlot.position.x, chosenSlot.position.y + randomHeight, chosenSlot.position.z);
+
+                GameObject collectible = Instantiate(gearPrefab, spawnPosition, gearPrefab.transform.rotation);
+                collectible.transform.SetParent(chosenSlot, true); 
             }
         }
     }