diff --git a/tests/audit_math_tests/__init__.py b/tests/audit_math_tests/__init__.py
new file mode 100644
index 000000000..e69de29bb
diff --git a/tests/routes_tests/__init__.py b/tests/routes_tests/__init__.py
new file mode 100644
index 000000000..e69de29bb
diff --git a/tests/routes_tests/test_audit_boards.py b/tests/routes_tests/test_audit_boards.py
index 7736d576d..3faf9b6bb 100644
--- a/tests/routes_tests/test_audit_boards.py
+++ b/tests/routes_tests/test_audit_boards.py
@@ -1,6 +1,6 @@
 import pytest, json
 from flask.testing import FlaskClient
-from typing import List
+from typing import List, Generator
 from datetime import datetime
 from collections import defaultdict
 
@@ -74,7 +74,7 @@ def round_id(
     contest_id: str,  # pylint: disable=unused-argument
     election_settings,  # pylint: disable=unused-argument
     manifests,  # pylint: disable=unused-argument
-) -> str:
+) -> Generator[str, None, None]:
     rv = post_json(
         client,
         f"/election/{election_id}/round",
@@ -89,7 +89,7 @@ def round_id(
 @pytest.fixture
 def round_2_id(
     client: FlaskClient, election_id: str, contest_id: str, round_id: str,
-) -> str:
+) -> Generator[str, None, None]:
     # Fake that the first round got completed by setting Round.ended_at.
     # We also need to add RoundContestResults so that the next round sample
     # size can get computed.
diff --git a/tests/routes_tests/test_audit_status.py b/tests/routes_tests/test_audit_status.py
index 51bb9cd4e..f919386e8 100644
--- a/tests/routes_tests/test_audit_status.py
+++ b/tests/routes_tests/test_audit_status.py
@@ -1,6 +1,7 @@
 import json
 import pytest
 from flask.testing import FlaskClient
+from typing import Generator
 
 from tests.helpers import (
     compare_json,
@@ -14,7 +15,7 @@
 
 
 @pytest.fixture()
-def election_id(client: FlaskClient) -> str:
+def election_id(client: FlaskClient) -> Generator[str, None, None]:
     yield create_election(client, is_multi_jurisdiction=False)
 
 
diff --git a/tests/routes_tests/test_auth.py b/tests/routes_tests/test_auth.py
index 117a3d793..090eb64b3 100644
--- a/tests/routes_tests/test_auth.py
+++ b/tests/routes_tests/test_auth.py
@@ -130,7 +130,7 @@ def test_auditadmin_callback(
     rv = client.get("/auth/auditadmin/callback?code=foobar")
     assert rv.status_code == 302
 
-    with client.session_transaction() as session:
+    with client.session_transaction() as session:  # type: ignore
         assert session["_user"]["type"] == UserType.AUDIT_ADMIN
         assert session["_user"]["email"] == AA_EMAIL
 
@@ -155,7 +155,7 @@ def test_jurisdictionadmin_callback(
     rv = client.get("/auth/jurisdictionadmin/callback?code=foobar")
     assert rv.status_code == 302
 
-    with client.session_transaction() as session:
+    with client.session_transaction() as session:  # type: ignore
         assert session["_user"]["type"] == UserType.JURISDICTION_ADMIN
         assert session["_user"]["email"] == JA_EMAIL
 
@@ -168,7 +168,7 @@ def test_logout(client: FlaskClient):
 
     rv = client.get("/auth/logout")
 
-    with client.session_transaction() as session:
+    with client.session_transaction() as session:  # type: ignore
         assert session["_user"] is None
 
     assert rv.status_code == 302
diff --git a/tests/routes_tests/test_ballot_list.py b/tests/routes_tests/test_ballot_list.py
index bc46a2809..46a4e84ec 100644
--- a/tests/routes_tests/test_ballot_list.py
+++ b/tests/routes_tests/test_ballot_list.py
@@ -1,6 +1,6 @@
 import json
 from flask.testing import FlaskClient
-
+from typing import Generator
 import pytest
 
 from tests.helpers import assert_ok, post_json, create_election
@@ -9,7 +9,7 @@
 
 
 @pytest.fixture()
-def election_id(client: FlaskClient) -> str:
+def election_id(client: FlaskClient) -> Generator[str, None, None]:
     yield create_election(client, is_multi_jurisdiction=False)
 
 
diff --git a/tests/routes_tests/test_contests.py b/tests/routes_tests/test_contests.py
index 277041ff3..107432be8 100644
--- a/tests/routes_tests/test_contests.py
+++ b/tests/routes_tests/test_contests.py
@@ -183,7 +183,7 @@ def test_contests_round_status(
 def test_contests_missing_field(
     client: FlaskClient, election_id: str, jurisdiction_ids: List[str]
 ):
-    contest = {
+    contest: JSONDict = {
         "id": str(uuid.uuid4()),
         "name": "Contest 1",
         "isTargeted": True,
diff --git a/tests/routes_tests/test_report.py b/tests/routes_tests/test_report.py
index 076fabbc5..b3c140d50 100644
--- a/tests/routes_tests/test_report.py
+++ b/tests/routes_tests/test_report.py
@@ -1,6 +1,6 @@
 import json, random
 from flask.testing import FlaskClient
-
+from typing import Generator
 import pytest
 
 from tests.helpers import assert_ok, post_json, create_election
@@ -9,7 +9,7 @@
 
 
 @pytest.fixture()
-def election_id(client: FlaskClient) -> str:
+def election_id(client: FlaskClient) -> Generator[str, None, None]:
     yield create_election(client, is_multi_jurisdiction=False)
 
 
diff --git a/tests/util_tests/__init__.py b/tests/util_tests/__init__.py
new file mode 100644
index 000000000..e69de29bb
diff --git a/tests/util_tests/test_binpacking.py b/tests/util_tests/test_binpacking.py
index db9c3a3dc..d19cc6783 100644
--- a/tests/util_tests/test_binpacking.py
+++ b/tests/util_tests/test_binpacking.py
@@ -72,7 +72,7 @@ def test_init(self, bucket):
         )
         assert (
             not bucket.largest_element
-        ), "Initial largest element was not None".format(bucket.largest_element)
+        ), "Initial largest element was not None: {}".format(bucket.largest_element)
 
     def test_add_batch(self, bucket):
         expected_batches = {"1": 100}