diff --git a/IMPLEMENTATION_COVERAGE.md b/IMPLEMENTATION_COVERAGE.md
index c38ca5619..0d8bf7a73 100644
--- a/IMPLEMENTATION_COVERAGE.md
+++ b/IMPLEMENTATION_COVERAGE.md
@@ -6172,6 +6172,24 @@
 - [ ] update_workteam
 </details>
 
+## scheduler
+<details>
+<summary>100% implemented</summary>
+
+- [X] create_schedule
+- [X] create_schedule_group
+- [X] delete_schedule
+- [X] delete_schedule_group
+- [X] get_schedule
+- [X] get_schedule_group
+- [X] list_schedule_groups
+- [X] list_schedules
+- [X] list_tags_for_resource
+- [X] tag_resource
+- [X] untag_resource
+- [X] update_schedule
+</details>
+
 ## sdb
 <details>
 <summary>50% implemented</summary>
@@ -7081,7 +7099,6 @@
 - sagemaker-metrics
 - sagemaker-runtime
 - savingsplans
-- scheduler
 - schemas
 - securityhub
 - securitylake
diff --git a/docs/docs/services/scheduler.rst b/docs/docs/services/scheduler.rst
new file mode 100644
index 000000000..74fe1433f
--- /dev/null
+++ b/docs/docs/services/scheduler.rst
@@ -0,0 +1,58 @@
+.. _implementedservice_scheduler:
+
+.. |start-h3| raw:: html
+
+    <h3>
+
+.. |end-h3| raw:: html
+
+    </h3>
+
+=========
+scheduler
+=========
+
+.. autoclass:: moto.scheduler.models.EventBridgeSchedulerBackend
+
+|start-h3| Example usage |end-h3|
+
+.. sourcecode:: python
+
+            @mock_scheduler
+            def test_scheduler_behaviour:
+                boto3.client("scheduler")
+                ...
+
+
+
+|start-h3| Implemented features for this service |end-h3|
+
+- [X] create_schedule
+  
+        The ClientToken parameter is not yet implemented
+        
+
+- [X] create_schedule_group
+  
+        The ClientToken parameter is not yet implemented
+        
+
+- [X] delete_schedule
+- [X] delete_schedule_group
+- [X] get_schedule
+- [X] get_schedule_group
+- [X] list_schedule_groups
+  
+        The MaxResults-parameter and pagination options are not yet implemented
+        
+
+- [ ] list_schedules
+- [X] list_tags_for_resource
+- [X] tag_resource
+- [X] untag_resource
+- [X] update_schedule
+  
+        The ClientToken is not yet implemented
+        
+
+
diff --git a/moto/__init__.py b/moto/__init__.py
index 2ab5615e5..682906ec6 100644
--- a/moto/__init__.py
+++ b/moto/__init__.py
@@ -143,6 +143,7 @@ mock_route53resolver = lazy_load(
 mock_s3 = lazy_load(".s3", "mock_s3")
 mock_s3control = lazy_load(".s3control", "mock_s3control")
 mock_sagemaker = lazy_load(".sagemaker", "mock_sagemaker")
+mock_scheduler = lazy_load(".scheduler", "mock_scheduler")
 mock_sdb = lazy_load(".sdb", "mock_sdb")
 mock_secretsmanager = lazy_load(".secretsmanager", "mock_secretsmanager")
 mock_servicequotas = lazy_load(
diff --git a/moto/backend_index.py b/moto/backend_index.py
index 20cee8a4b..623777c19 100644
--- a/moto/backend_index.py
+++ b/moto/backend_index.py
@@ -148,6 +148,7 @@ backend_url_patterns = [
         re.compile("https?://([0-9]+)\\.s3-control\\.(.+)\\.amazonaws\\.com"),
     ),
     ("sagemaker", re.compile("https?://api\\.sagemaker\\.(.+)\\.amazonaws.com")),
+    ("scheduler", re.compile("https?://scheduler\\.(.+)\\.amazonaws\\.com")),
     ("sdb", re.compile("https?://sdb\\.(.+)\\.amazonaws\\.com")),
     ("secretsmanager", re.compile("https?://secretsmanager\\.(.+)\\.amazonaws\\.com")),
     (
diff --git a/moto/scheduler/__init__.py b/moto/scheduler/__init__.py
new file mode 100644
index 000000000..369fe0fa5
--- /dev/null
+++ b/moto/scheduler/__init__.py
@@ -0,0 +1,5 @@
+"""scheduler module initialization; sets value for base decorator."""
+from .models import scheduler_backends
+from ..core.models import base_decorator
+
+mock_scheduler = base_decorator(scheduler_backends)
diff --git a/moto/scheduler/exceptions.py b/moto/scheduler/exceptions.py
new file mode 100644
index 000000000..cb126594b
--- /dev/null
+++ b/moto/scheduler/exceptions.py
@@ -0,0 +1,12 @@
+"""Exceptions raised by the scheduler service."""
+from moto.core.exceptions import JsonRESTError
+
+
+class ScheduleNotFound(JsonRESTError):
+    def __init__(self) -> None:
+        super().__init__("ResourceNotFoundException", "Schedule not found")
+
+
+class ScheduleGroupNotFound(JsonRESTError):
+    def __init__(self) -> None:
+        super().__init__("ResourceNotFoundException", "ScheduleGroup not found")
diff --git a/moto/scheduler/models.py b/moto/scheduler/models.py
new file mode 100644
index 000000000..9e1df7739
--- /dev/null
+++ b/moto/scheduler/models.py
@@ -0,0 +1,240 @@
+"""EventBridgeSchedulerBackend class with methods for supported APIs."""
+from typing import Any, Dict, List, Iterable, Optional
+
+from moto.core import BaseBackend, BackendDict, BaseModel
+from moto.core.utils import unix_time
+from moto.utilities.tagging_service import TaggingService
+
+from .exceptions import ScheduleNotFound, ScheduleGroupNotFound
+
+
+class Schedule(BaseModel):
+    def __init__(
+        self,
+        region: str,
+        account_id: str,
+        group_name: str,
+        name: str,
+        description: Optional[str],
+        schedule_expression: str,
+        schedule_expression_timezone: Optional[str],
+        flexible_time_window: Dict[str, Any],
+        target: Dict[str, Any],
+        state: Optional[str],
+        kms_key_arn: Optional[str],
+        start_date: Optional[str],
+        end_date: Optional[str],
+    ):
+        self.name = name
+        self.group_name = group_name
+        self.description = description
+        self.arn = (
+            f"arn:aws:scheduler:{region}:{account_id}:schedule/{group_name}/{name}"
+        )
+        self.schedule_expression = schedule_expression
+        self.schedule_expression_timezone = schedule_expression_timezone
+        self.flexible_time_window = flexible_time_window
+        self.target = Schedule.validate_target(target)
+        self.state = state or "ENABLED"
+        self.kms_key_arn = kms_key_arn
+        self.start_date = start_date
+        self.end_date = end_date
+
+    @staticmethod
+    def validate_target(target: Dict[str, Any]) -> Dict[str, Any]:  # type: ignore[misc]
+        if "RetryPolicy" not in target:
+            target["RetryPolicy"] = {
+                "MaximumEventAgeInSeconds": 86400,
+                "MaximumRetryAttempts": 185,
+            }
+        return target
+
+    def to_dict(self, short: bool = False) -> Dict[str, Any]:
+        dct: Dict[str, Any] = {
+            "Arn": self.arn,
+            "Name": self.name,
+            "GroupName": self.group_name,
+            "Description": self.description,
+            "ScheduleExpression": self.schedule_expression,
+            "ScheduleExpressionTimezone": self.schedule_expression_timezone,
+            "FlexibleTimeWindow": self.flexible_time_window,
+            "Target": self.target,
+            "State": self.state,
+            "KmsKeyArn": self.kms_key_arn,
+            "StartDate": self.start_date,
+            "EndDate": self.end_date,
+        }
+        if short:
+            dct["Target"] = {"Arn": dct["Target"]["Arn"]}
+        return dct
+
+
+class ScheduleGroup(BaseModel):
+    def __init__(self, region: str, account_id: str, name: str):
+        self.name = name
+        self.arn = f"arn:aws:scheduler:{region}:{account_id}:schedule-group/{name}"
+        self.schedules: Dict[str, Schedule] = dict()
+        self.created_on = None if self.name == "default" else unix_time()
+        self.last_modified = None if self.name == "default" else unix_time()
+
+    def add_schedule(self, schedule: Schedule) -> None:
+        self.schedules[schedule.name] = schedule
+
+    def get_schedule(self, name: str) -> Schedule:
+        if name not in self.schedules:
+            raise ScheduleNotFound
+        return self.schedules[name]
+
+    def delete_schedule(self, name: str) -> None:
+        self.schedules.pop(name)
+
+    def to_dict(self) -> Dict[str, Any]:
+        return {
+            "Arn": self.arn,
+            "CreationDate": self.created_on,
+            "LastModificationDate": self.last_modified,
+            "Name": self.name,
+            "State": "ACTIVE",
+        }
+
+
+class EventBridgeSchedulerBackend(BaseBackend):
+    """Implementation of EventBridgeScheduler APIs."""
+
+    def __init__(self, region_name: str, account_id: str):
+        super().__init__(region_name, account_id)
+        self.schedules: List[Schedule] = list()
+        self.schedule_groups = {
+            "default": ScheduleGroup(
+                region=region_name, account_id=account_id, name="default"
+            )
+        }
+        self.tagger = TaggingService()
+
+    def create_schedule(
+        self,
+        description: str,
+        end_date: str,
+        flexible_time_window: Dict[str, Any],
+        group_name: str,
+        kms_key_arn: str,
+        name: str,
+        schedule_expression: str,
+        schedule_expression_timezone: str,
+        start_date: str,
+        state: str,
+        target: Dict[str, Any],
+    ) -> Schedule:
+        """
+        The ClientToken parameter is not yet implemented
+        """
+        group = self.schedule_groups[group_name or "default"]
+        schedule = Schedule(
+            region=self.region_name,
+            account_id=self.account_id,
+            group_name=group.name,
+            name=name,
+            description=description,
+            schedule_expression=schedule_expression,
+            schedule_expression_timezone=schedule_expression_timezone,
+            flexible_time_window=flexible_time_window,
+            target=target,
+            state=state,
+            kms_key_arn=kms_key_arn,
+            start_date=start_date,
+            end_date=end_date,
+        )
+        group.add_schedule(schedule)
+        return schedule
+
+    def get_schedule(self, group_name: Optional[str], name: str) -> Schedule:
+        group = self.get_schedule_group(group_name)
+        return group.get_schedule(name)
+
+    def delete_schedule(self, group_name: Optional[str], name: str) -> None:
+        group = self.get_schedule_group(group_name)
+        group.delete_schedule(name)
+
+    def update_schedule(
+        self,
+        description: str,
+        end_date: str,
+        flexible_time_window: Dict[str, Any],
+        group_name: str,
+        kms_key_arn: str,
+        name: str,
+        schedule_expression: str,
+        schedule_expression_timezone: str,
+        start_date: str,
+        state: str,
+        target: Dict[str, Any],
+    ) -> Schedule:
+        """
+        The ClientToken is not yet implemented
+        """
+        schedule = self.get_schedule(group_name=group_name, name=name)
+        schedule.schedule_expression = schedule_expression
+        schedule.schedule_expression_timezone = schedule_expression_timezone
+        schedule.flexible_time_window = flexible_time_window
+        schedule.target = Schedule.validate_target(target)
+        schedule.description = description
+        schedule.state = state
+        schedule.kms_key_arn = kms_key_arn
+        schedule.start_date = start_date
+        schedule.end_date = end_date
+        return schedule
+
+    def list_schedules(
+        self, group_names: Optional[str], state: Optional[str]
+    ) -> Iterable[Schedule]:
+        """
+        The following parameters are not yet implemented: MaxResults, NamePrefix, NextToken
+        """
+        results = []
+        for group in self.schedule_groups.values():
+            if not group_names or group.name in group_names:
+                for schedule in group.schedules.values():
+                    if not state or schedule.state == state:
+                        results.append(schedule)
+        return results
+
+    def create_schedule_group(
+        self, name: str, tags: List[Dict[str, str]]
+    ) -> ScheduleGroup:
+        """
+        The ClientToken parameter is not yet implemented
+        """
+        group = ScheduleGroup(
+            region=self.region_name, account_id=self.account_id, name=name
+        )
+        self.schedule_groups[name] = group
+        self.tagger.tag_resource(group.arn, tags)
+        return group
+
+    def get_schedule_group(self, group_name: Optional[str]) -> ScheduleGroup:
+        if (group_name or "default") not in self.schedule_groups:
+            raise ScheduleGroupNotFound
+        return self.schedule_groups[group_name or "default"]
+
+    def list_schedule_groups(self) -> Iterable[ScheduleGroup]:
+        """
+        The MaxResults-parameter and pagination options are not yet implemented
+        """
+        return self.schedule_groups.values()
+
+    def delete_schedule_group(self, name: Optional[str]) -> None:
+        self.schedule_groups.pop(name or "default")
+
+    def list_tags_for_resource(
+        self, resource_arn: str
+    ) -> Dict[str, List[Dict[str, str]]]:
+        return self.tagger.list_tags_for_resource(resource_arn)
+
+    def tag_resource(self, resource_arn: str, tags: List[Dict[str, str]]) -> None:
+        self.tagger.tag_resource(resource_arn, tags)
+
+    def untag_resource(self, resource_arn: str, tag_keys: List[str]) -> None:
+        self.tagger.untag_resource_using_names(resource_arn, tag_keys)
+
+
+scheduler_backends = BackendDict(EventBridgeSchedulerBackend, "scheduler")
diff --git a/moto/scheduler/responses.py b/moto/scheduler/responses.py
new file mode 100644
index 000000000..9517840e6
--- /dev/null
+++ b/moto/scheduler/responses.py
@@ -0,0 +1,142 @@
+"""Handles incoming scheduler requests, invokes methods, returns responses."""
+import json
+from typing import Any
+from urllib.parse import unquote
+
+from moto.core.common_types import TYPE_RESPONSE
+from moto.core.responses import BaseResponse
+from .models import scheduler_backends, EventBridgeSchedulerBackend
+
+
+class EventBridgeSchedulerResponse(BaseResponse):
+    """Handler for EventBridgeScheduler requests and responses."""
+
+    def __init__(self) -> None:
+        super().__init__(service_name="scheduler")
+
+    @property
+    def scheduler_backend(self) -> EventBridgeSchedulerBackend:
+        """Return backend instance specific for this region."""
+        return scheduler_backends[self.current_account][self.region]
+
+    def create_schedule(self) -> str:
+        description = self._get_param("Description")
+        end_date = self._get_param("EndDate")
+        flexible_time_window = self._get_param("FlexibleTimeWindow")
+        group_name = self._get_param("GroupName")
+        kms_key_arn = self._get_param("KmsKeyArn")
+        name = self.uri.split("/")[-1]
+        schedule_expression = self._get_param("ScheduleExpression")
+        schedule_expression_timezone = self._get_param("ScheduleExpressionTimezone")
+        start_date = self._get_param("StartDate")
+        state = self._get_param("State")
+        target = self._get_param("Target")
+        schedule = self.scheduler_backend.create_schedule(
+            description=description,
+            end_date=end_date,
+            flexible_time_window=flexible_time_window,
+            group_name=group_name,
+            kms_key_arn=kms_key_arn,
+            name=name,
+            schedule_expression=schedule_expression,
+            schedule_expression_timezone=schedule_expression_timezone,
+            start_date=start_date,
+            state=state,
+            target=target,
+        )
+        return json.dumps(dict(ScheduleArn=schedule.arn))
+
+    def get_schedule(self) -> str:
+        group_name = self._get_param("groupName")
+        full_url = self.uri.split("?")[0]
+        name = full_url.split("/")[-1]
+        schedule = self.scheduler_backend.get_schedule(group_name, name)
+        return json.dumps(schedule.to_dict())
+
+    def delete_schedule(self) -> str:
+        group_name = self._get_param("groupName")
+        name = self.uri.split("?")[0].split("/")[-1]
+        self.scheduler_backend.delete_schedule(group_name, name)
+        return "{}"
+
+    def update_schedule(self) -> str:
+        group_name = self._get_param("groupName")
+        name = self.uri.split("?")[0].split("/")[-1]
+        description = self._get_param("Description")
+        end_date = self._get_param("EndDate")
+        flexible_time_window = self._get_param("FlexibleTimeWindow")
+        kms_key_arn = self._get_param("KmsKeyArn")
+        schedule_expression = self._get_param("ScheduleExpression")
+        schedule_expression_timezone = self._get_param("ScheduleExpressionTimezone")
+        start_date = self._get_param("StartDate")
+        state = self._get_param("State")
+        target = self._get_param("Target")
+        schedule = self.scheduler_backend.update_schedule(
+            description=description,
+            end_date=end_date,
+            flexible_time_window=flexible_time_window,
+            group_name=group_name,
+            kms_key_arn=kms_key_arn,
+            name=name,
+            schedule_expression=schedule_expression,
+            schedule_expression_timezone=schedule_expression_timezone,
+            start_date=start_date,
+            state=state,
+            target=target,
+        )
+        return json.dumps(dict(ScheduleArn=schedule.arn))
+
+    def list_schedules(self) -> str:
+        group_names = self.querystring.get("ScheduleGroup")
+        state = self._get_param("State")
+        schedules = self.scheduler_backend.list_schedules(group_names, state)
+        return json.dumps({"Schedules": [sch.to_dict(short=True) for sch in schedules]})
+
+    def create_schedule_group(self) -> str:
+        name = self._get_param("Name")
+        tags = self._get_param("Tags")
+        schedule_group = self.scheduler_backend.create_schedule_group(
+            name=name,
+            tags=tags,
+        )
+        return json.dumps(dict(ScheduleGroupArn=schedule_group.arn))
+
+    def get_schedule_group(self) -> str:
+        group_name = self.uri.split("?")[0].split("/")[-1]
+        group = self.scheduler_backend.get_schedule_group(group_name)
+        return json.dumps(group.to_dict())
+
+    def delete_schedule_group(self) -> str:
+        group_name = self.uri.split("?")[0].split("/")[-1]
+        self.scheduler_backend.delete_schedule_group(group_name)
+        return "{}"
+
+    def list_schedule_groups(self) -> str:
+        schedule_groups = self.scheduler_backend.list_schedule_groups()
+        return json.dumps(dict(ScheduleGroups=[sg.to_dict() for sg in schedule_groups]))
+
+    def list_tags_for_resource(self) -> TYPE_RESPONSE:
+        resource_arn = unquote(self.uri.split("/tags/")[-1])
+        tags = self.scheduler_backend.list_tags_for_resource(resource_arn)
+        return 200, {}, json.dumps(tags)
+
+    def tag_resource(self) -> TYPE_RESPONSE:
+        resource_arn = unquote(self.uri.split("/tags/")[-1])
+        tags = json.loads(self.body)["Tags"]
+        self.scheduler_backend.tag_resource(resource_arn, tags)
+        return 200, {}, "{}"
+
+    def untag_resource(self) -> TYPE_RESPONSE:
+        resource_arn = unquote(self.uri.split("?")[0].split("/tags/")[-1])
+        tag_keys = self.querystring.get("TagKeys")
+        self.scheduler_backend.untag_resource(resource_arn, tag_keys)  # type: ignore
+        return 200, {}, "{}"
+
+    def tags(self, request: Any, full_url: str, headers: Any) -> TYPE_RESPONSE:
+        super().setup_class(request, full_url, headers)
+        if request.method == "POST":
+            return self.tag_resource()
+        elif request.method == "DELETE":
+            return self.untag_resource()
+        else:
+            return self.list_tags_for_resource()
diff --git a/moto/scheduler/urls.py b/moto/scheduler/urls.py
new file mode 100644
index 000000000..ddd71fa77
--- /dev/null
+++ b/moto/scheduler/urls.py
@@ -0,0 +1,19 @@
+"""scheduler base URL and path."""
+from .responses import EventBridgeSchedulerResponse
+
+url_bases = [
+    r"https?://scheduler\.(.+)\.amazonaws\.com",
+]
+
+
+response = EventBridgeSchedulerResponse()
+
+
+url_paths = {
+    "{0}/schedules$": response.dispatch,
+    "{0}/schedules/(?P<name>[^/]+)$": response.dispatch,
+    "{0}/schedule-groups$": response.dispatch,
+    "{0}/schedule-groups/(?P<name>[^/]+)$": response.dispatch,
+    "{0}/tags/(?P<ResourceArn>.+)$": response.tags,
+    "{0}/tags/arn:aws:scheduler:(?P<region_name>[^/]+):(?P<account_id>[^/]+):schedule/(?P<group_name>[^/]+)/(?P<schedule_name>[^/]+)/?$": response.tags,
+}
diff --git a/setup.cfg b/setup.cfg
index 2f4529ffb..ec3d9b04c 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -235,7 +235,7 @@ disable = W,C,R,E
 enable = anomalous-backslash-in-string, arguments-renamed, dangerous-default-value, deprecated-module, function-redefined, import-self, redefined-builtin, redefined-outer-name, reimported, pointless-statement, super-with-arguments, unused-argument, unused-import, unused-variable, useless-else-on-loop, wildcard-import
 
 [mypy]
-files= moto/a*,moto/b*,moto/c*,moto/d*,moto/e*,moto/f*,moto/g*,moto/i*,moto/k*,moto/l*,moto/m*,moto/n*,moto/o*,moto/p*,moto/q*,moto/rdsdata
+files= moto/a*,moto/b*,moto/c*,moto/d*,moto/e*,moto/f*,moto/g*,moto/i*,moto/k*,moto/l*,moto/m*,moto/n*,moto/o*,moto/p*,moto/q*,moto/rdsdata,moto/scheduler
 show_column_numbers=True
 show_error_codes = True
 disable_error_code=abstract
diff --git a/tests/terraformtests/terraform-tests.success.txt b/tests/terraformtests/terraform-tests.success.txt
index 11c70d14f..7011067bb 100644
--- a/tests/terraformtests/terraform-tests.success.txt
+++ b/tests/terraformtests/terraform-tests.success.txt
@@ -494,6 +494,9 @@ s3:
   - TestAccS3ObjectsDataSource_fetchOwner
 sagemaker:
   - TestAccSageMakerPrebuiltECRImageDataSource
+scheduler:
+  - TestAccSchedulerSchedule_
+  - TestAccSchedulerScheduleGroup_
 secretsmanager:
   - TestAccSecretsManagerSecretDataSource_basic
   - TestAccSecretsManagerSecretPolicy_
diff --git a/tests/test_scheduler/__init__.py b/tests/test_scheduler/__init__.py
new file mode 100644
index 000000000..e69de29bb
diff --git a/tests/test_scheduler/test_schedule_groups.py b/tests/test_scheduler/test_schedule_groups.py
new file mode 100644
index 000000000..ced28e4af
--- /dev/null
+++ b/tests/test_scheduler/test_schedule_groups.py
@@ -0,0 +1,49 @@
+"""Unit tests for scheduler-supported APIs."""
+import boto3
+import pytest
+
+from botocore.exceptions import ClientError
+from moto import mock_scheduler
+from moto.core import DEFAULT_ACCOUNT_ID
+
+# See our Development Tips on writing tests for hints on how to write good tests:
+# http://docs.getmoto.org/en/latest/docs/contributing/development_tips/tests.html
+
+
+@mock_scheduler
+def test_create_get_delete_schedule_group():
+    client = boto3.client("scheduler", region_name="eu-west-1")
+    arn = client.create_schedule_group(Name="sg")["ScheduleGroupArn"]
+
+    assert arn == f"arn:aws:scheduler:eu-west-1:{DEFAULT_ACCOUNT_ID}:schedule-group/sg"
+
+    group = client.get_schedule_group(Name="sg")
+    assert group["Arn"] == arn
+    assert group["Name"] == "sg"
+    assert group["State"] == "ACTIVE"
+
+    client.delete_schedule_group(Name="sg")
+
+    with pytest.raises(ClientError) as exc:
+        client.get_schedule_group(Name="sg")
+    err = exc.value.response["Error"]
+    assert err["Code"] == "ResourceNotFoundException"
+
+
+@mock_scheduler
+def test_list_schedule_groups():
+    client = boto3.client("scheduler", region_name="ap-southeast-1")
+
+    # The default group is always active
+    groups = client.list_schedule_groups()["ScheduleGroups"]
+    assert len(groups) == 1
+    assert (
+        groups[0]["Arn"]
+        == f"arn:aws:scheduler:ap-southeast-1:{DEFAULT_ACCOUNT_ID}:schedule-group/default"
+    )
+
+    arn1 = client.create_schedule_group(Name="sg")["ScheduleGroupArn"]
+
+    groups = client.list_schedule_groups()["ScheduleGroups"]
+    assert len(groups) == 2
+    assert groups[1]["Arn"] == arn1
diff --git a/tests/test_scheduler/test_scheduler.py b/tests/test_scheduler/test_scheduler.py
new file mode 100644
index 000000000..5531a3b0f
--- /dev/null
+++ b/tests/test_scheduler/test_scheduler.py
@@ -0,0 +1,167 @@
+"""Unit tests for scheduler-supported APIs."""
+import boto3
+import pytest
+
+from botocore.client import ClientError
+from moto import mock_scheduler
+from moto.core import DEFAULT_ACCOUNT_ID
+
+# See our Development Tips on writing tests for hints on how to write good tests:
+# http://docs.getmoto.org/en/latest/docs/contributing/development_tips/tests.html
+
+
+@mock_scheduler
+def test_create_get_schedule():
+    client = boto3.client("scheduler", region_name="eu-west-1")
+    arn = client.create_schedule(
+        Name="my-schedule",
+        ScheduleExpression="some cron",
+        FlexibleTimeWindow={
+            "MaximumWindowInMinutes": 4,
+            "Mode": "OFF",
+        },
+        Target={
+            "Arn": "not supported yet",
+            "RoleArn": "n/a",
+        },
+    )["ScheduleArn"]
+
+    assert (
+        arn
+        == f"arn:aws:scheduler:eu-west-1:{DEFAULT_ACCOUNT_ID}:schedule/default/my-schedule"
+    )
+
+    resp = client.get_schedule(Name="my-schedule")
+    assert resp["Arn"] == arn
+    assert resp["Name"] == "my-schedule"
+    assert resp["ScheduleExpression"] == "some cron"
+    assert resp["FlexibleTimeWindow"] == {
+        "MaximumWindowInMinutes": 4,
+        "Mode": "OFF",
+    }
+    assert resp["Target"] == {
+        "Arn": "not supported yet",
+        "RoleArn": "n/a",
+        "RetryPolicy": {"MaximumEventAgeInSeconds": 86400, "MaximumRetryAttempts": 185},
+    }
+
+
+@mock_scheduler
+def test_create_get_delete__in_different_group():
+    client = boto3.client("scheduler", region_name="eu-west-1")
+
+    client.create_schedule_group(Name="sg")
+    schedule_arn = client.create_schedule(
+        Name="my-schedule",
+        GroupName="sg",
+        ScheduleExpression="some cron",
+        FlexibleTimeWindow={
+            "MaximumWindowInMinutes": 4,
+            "Mode": "OFF",
+        },
+        Target={
+            "Arn": "not supported yet",
+            "RoleArn": "n/a",
+        },
+    )["ScheduleArn"]
+
+    assert (
+        schedule_arn
+        == "arn:aws:scheduler:eu-west-1:123456789012:schedule/sg/my-schedule"
+    )
+
+    schedule = client.get_schedule(GroupName="sg", Name="my-schedule")
+    assert schedule["Arn"] == schedule_arn
+
+    client.delete_schedule(GroupName="sg", Name="my-schedule")
+
+    with pytest.raises(ClientError) as exc:
+        client.get_schedule(GroupName="sg", Name="my-schedule")
+    err = exc.value.response["Error"]
+    assert err["Code"] == "ResourceNotFoundException"
+
+
+@mock_scheduler
+def test_update_schedule():
+    client = boto3.client("scheduler", region_name="eu-west-1")
+
+    client.create_schedule(
+        Name="my-schedule",
+        ScheduleExpression="some cron",
+        FlexibleTimeWindow={
+            "MaximumWindowInMinutes": 4,
+            "Mode": "OFF",
+        },
+        Target={
+            "Arn": "not supported yet",
+            "RoleArn": "n/a",
+        },
+    )
+
+    client.update_schedule(
+        Name="my-schedule",
+        Description="new desc",
+        ScheduleExpression="new cron",
+        FlexibleTimeWindow={
+            "MaximumWindowInMinutes": 4,
+            "Mode": "OFF",
+        },
+        State="DISABLED",
+        Target={
+            "Arn": "different arn",
+            "RoleArn": "n/a",
+        },
+    )
+
+    schedule = client.get_schedule(Name="my-schedule")
+    assert schedule["Description"] == "new desc"
+    assert schedule["ScheduleExpression"] == "new cron"
+    assert schedule["State"] == "DISABLED"
+    assert schedule["Target"] == {
+        "Arn": "different arn",
+        "RoleArn": "n/a",
+        "RetryPolicy": {"MaximumEventAgeInSeconds": 86400, "MaximumRetryAttempts": 185},
+    }
+
+
+@mock_scheduler
+def test_get_schedule_for_unknown_group():
+    client = boto3.client("scheduler", region_name="eu-west-1")
+
+    with pytest.raises(ClientError) as exc:
+        client.get_schedule(GroupName="unknown", Name="my-schedule")
+    err = exc.value.response["Error"]
+    assert err["Code"] == "ResourceNotFoundException"
+
+
+@mock_scheduler
+def test_list_schedules():
+    client = boto3.client("scheduler", region_name="eu-west-1")
+
+    schedules = client.list_schedules()["Schedules"]
+    assert schedules == []
+
+    client.create_schedule_group(Name="group2")
+
+    for group in ["default", "group2"]:
+        for schedule in ["sch1", "sch2"]:
+            for state in ["ENABLED", "DISABLED"]:
+                client.create_schedule(
+                    Name=f"{schedule}_{state}",
+                    GroupName=group,
+                    State=state,
+                    ScheduleExpression="some cron",
+                    FlexibleTimeWindow={"MaximumWindowInMinutes": 4, "Mode": "OFF"},
+                    Target={"Arn": "not supported yet", "RoleArn": "n/a"},
+                )
+
+    schedules = client.list_schedules()["Schedules"]
+    assert len(schedules) == 8
+    # The ListSchedules command should not return the entire Target-dictionary
+    assert schedules[0]["Target"] == {"Arn": "not supported yet"}
+
+    schedules = client.list_schedules(GroupName="group2")["Schedules"]
+    assert len(schedules) == 4
+
+    schedules = client.list_schedules(State="ENABLED")["Schedules"]
+    assert len(schedules) == 4
diff --git a/tests/test_scheduler/test_scheduler_tags.py b/tests/test_scheduler/test_scheduler_tags.py
new file mode 100644
index 000000000..c1c7d25d0
--- /dev/null
+++ b/tests/test_scheduler/test_scheduler_tags.py
@@ -0,0 +1,57 @@
+import boto3
+
+from moto import mock_scheduler
+
+
+@mock_scheduler
+def test_schedule_tags():
+    client = boto3.client("scheduler", "us-east-1")
+    arn = client.create_schedule(
+        Name="my-schedule",
+        ScheduleExpression="some cron",
+        FlexibleTimeWindow={
+            "MaximumWindowInMinutes": 4,
+            "Mode": "OFF",
+        },
+        Target={
+            "Arn": "not supported yet",
+            "RoleArn": "n/a",
+        },
+    )["ScheduleArn"]
+
+    resp = client.list_tags_for_resource(ResourceArn=arn)
+    assert resp["Tags"] == []
+
+    client.tag_resource(
+        ResourceArn=arn,
+        Tags=[{"Key": "k1", "Value": "v1"}, {"Key": "k2", "Value": "v2"}],
+    )
+
+    resp = client.list_tags_for_resource(ResourceArn=arn)
+    assert resp["Tags"] == [{"Key": "k1", "Value": "v1"}, {"Key": "k2", "Value": "v2"}]
+
+    client.untag_resource(ResourceArn=arn, TagKeys=["k1"])
+
+    resp = client.list_tags_for_resource(ResourceArn=arn)
+    assert resp["Tags"] == [{"Key": "k2", "Value": "v2"}]
+
+
+@mock_scheduler
+def test_schedule_group_tags():
+    client = boto3.client("scheduler", "us-east-1")
+    arn = client.create_schedule_group(
+        Name="my-schedule", Tags=[{"Key": "k1", "Value": "v1"}]
+    )["ScheduleGroupArn"]
+
+    resp = client.list_tags_for_resource(ResourceArn=arn)
+    assert resp["Tags"] == [{"Key": "k1", "Value": "v1"}]
+
+    client.tag_resource(ResourceArn=arn, Tags=[{"Key": "k2", "Value": "v2"}])
+
+    resp = client.list_tags_for_resource(ResourceArn=arn)
+    assert resp["Tags"] == [{"Key": "k1", "Value": "v1"}, {"Key": "k2", "Value": "v2"}]
+
+    client.untag_resource(ResourceArn=arn, TagKeys=["k1"])
+
+    resp = client.list_tags_for_resource(ResourceArn=arn)
+    assert resp["Tags"] == [{"Key": "k2", "Value": "v2"}]
diff --git a/tests/test_scheduler/test_server.py b/tests/test_scheduler/test_server.py
new file mode 100644
index 000000000..3e7ef2f42
--- /dev/null
+++ b/tests/test_scheduler/test_server.py
@@ -0,0 +1,10 @@
+from moto import server as server
+
+
+def test_list_tags():
+    test_client = server.create_backend_app("scheduler").test_client()
+    res = test_client.get(
+        "/tags/arn%3Aaws%3Ascheduler%3Aus-east-1%3A123456789012%3Aschedule%2Fdefault%2Fmy-schedule"
+    )
+
+    assert res.data == b'{"Tags": []}'